Well, having a low frequency single chip is not much of a heat load. My W8000 has two Netburst 2.8GHz chips and it's noise is a lot more tolerable than my G5.
At any rate, I haven't seen much an argument why moving the power supply for the Mac Pros would be a bad thing.
I didn't know that my argument was about it being a "bad" thing. I just said it wasn't a very elegant or apple-like thing. There's already a well-designed heat removal system in the G5 case. Why futz with it when it's not necessary, and only adds to the rear panel clutter and cord knotting?
I don't think apple can do quad for $2K. But I think they can do conroe for $1500, maybe even less if they go minitower on the low end. Apple needs speed on the high end. On the low end, price is way more important than speed - people will complain more about a base model being too expensive than it not being fast enough.
Somewhere on this board, I worked out a way to get components for a 2 x 2.00 cost about $1700 w/ decent volume discounts. Apple picks a margin between 12.5 percent and 25 percent, and that computer costs between $2000 and $2200. It'd also be the best-selling workstation ever, because Dell's margins are off the charts in the workstation market.
I have to run, but I'll re-post that config tonight.
I ceded in another comment that "conductor" was a poor choice of words on my part, when I meant to say something along the lines of thermal retention.
Aluminum will heat up very quickly, but it cools down just as fast. That's why it's used a lot in bakeware rather than cookware -- where most times it's in a situation where there's surrounding or convection heat and it's just used to hold something or form a shape, as opposed to cooking it.
That's not correct.
Aluminum is used in cookware all of the time. It's used by itself, and it's used in conjunction with stainless steel, for protection.
The fact that aluminum heats up quickly means it is a good conductor as well. Thermal and electrical conductivity go hand in hand.
Aluminum, as a good conductor, allows the heat to quickly spread to the rest of the piece when one part is heated.
The reason why baking pans, aluminum foil, and heatsinks cool down quickly is because the metal is thin for the purpose. When metal is thin, there is is a high ratio of surface area to volume. That allows the heat to escape quickly. That will occur with any metal that is uniformly heated.
By the way, being a poor conductor does not mean that something is an insulator.
Glass is not a poor conductor, it is an insulator. Lead is not an insulator, it is a poor conductor.
Aluminum is used in cookware all of the time. It's used by itself, and it's used in conjunction with stainless steel, for protection.
Protection from what? Aluminum and aluminum core cookware is aimed at the consumer market because it doesn't tarnish, it heats up quickly and it's lightweight. It is however, something you will rarely ever see a professional chef use on a cooktop. Anyone fresh out of culinary school will tell you that. I dare you to find me a professional chef who does use solid aluminum pans.
Quote:
Aluminum, as a good conductor, allows the heat to quickly spread to the rest of the piece when one part is heated.
If something conducts temperature change well, it works both directions. If it heats up fast, it will cool down fast. Aluminum doesn't break these rules of thermodynamics. It will not have the same kind of uniform temperature the way that Iron, Steel, Copper or other metals have.
Quote:
The reason why baking pans, aluminum foil, and heatsinks cool down quickly is because the metal is thin for the purpose. When metal is thin, there is is a high ratio of surface area to volume. That allows the heat to escape quickly. That will occur with any metal that is uniformly heated.
And "uniformly heated" is debatable. It's much harder to get an accurate uniform heating of an aluminum pan. Aluminum does not retain heat as well as other metals; that's why it's used in heatsinks and the scourge of professional chefs.
Quote:
By the way, being a poor conductor does not mean that something is an insulator.
This is an amazing discussion on cooking and thermal conductivity on a Mac forum on the new Mac Pro.
Might as well get some facts on the table with a link to some actual thermal conductivity with a little information even on cooking pot design and why a copper core can be used between stainless plates for a pot.
I would bet that there are professionals who use aluminum as this is the primary metal for Calphalon. (It is anodized to provide a protective coating.) Aluminum is horrible with the acidity of many foods and should never be used with tomato sauces.
Now about the thermal design of the G5. I think it is great that Apple actually took the time to design a case to compensate for the heat load of the G5. My early Dual 2 rarely gets loud in summer and is even quieter in Winter when the house is cooler. I will guess that the Quads really benefit from the segregation and fan speed control.
It will be interesting to see what is done with the new chips and the 'lower' thermal requirements. I would love to see high performance chips in the another passively cooled 'cube' / original mac design. Will it ever happen again?
[B]Protection from what? Aluminum and aluminum core cookware is aimed at the consumer market because it doesn't tarnish, it heats up quickly and it's lightweight. It is however, something you will rarely ever see a professional chef use on a cooktop. Anyone fresh out of culinary school will tell you that. I dare you to find me a professional chef who does use solid aluminum pans.
My oh my, you don't know much about cooking, do you?
Only the cheapest aluminum cookware is plain finish. Better quality mdels are anodized. Most high quality models, such as the All-Clad I have has a SS outer shell, a sandwitch of aluminum Aluminum, and an interior made up of SS again. Food acid, esp at high temps corrods aluminum, which is not considered to be healthy.
The All-Clad is the most popular line of cookware in restaurants.
Copper is used on the most expensive models, but has not been shown to be better. Look to the reviews of pro level cookware in Cook's Illustrated, Fine Cooking, and elseware.
Please don't make things up. People here know too much.
Quote:
If something conducts temperature change well, it works both directions. If it heats up fast, it will cool down fast. Aluminum doesn't break these rules of thermodynamics. It will not have the same kind of uniform temperature the way that Iron, Steel, Copper or other metals have.
And "uniformly heated" is debatable. It's much harder to get an accurate uniform heating of an aluminum pan. Aluminum does not retain heat as well as other metals; that's why it's used in heatsinks and the scourge of professional chefs.
It's used because of the reasons I already gave.
Quote:
I did not say it was an insulator.
Yes, I know, Jeff said it. I mentioned it in that post because we were talking about that subject.
The reason I've always heard given for the avoidance of aluminum in professional cookware is that it's too good of a conductor, and that any hotspots in your burner/heating element translate into local hotspots in your cookware.
Slightly poorer conductors will spread hotspots out more, using this same reasoning.
The reason I've always heard given for the avoidance of aluminum in professional cookware is that it's too good of a conductor, and that any hotspots in your burner/heating element translate into local hotspots in your cookware.
Slightly poorer conductors will spread hotspots out more, using this same reasoning.
That's why All-Clad (get the name?) invented the wrap around sandwich 30 years ago. Now, all other manufacturers have copied it.
It also depends upon the design itself. Good designs, such as All-Clad's, work very well. Some others, don't.
The reasoning you give is simply wrong. SS is a poor conductor, and makes poor cookware. Just the opposite of what you said happens.
If you think about it for a minute, you will see why. Poor conduction leads the spot above the flame to get hot, while the areas further away, stay relatively cool. Good conductivity allows that localized heat to spread out quickly, heating the cookware evenly.
That's why All-Clad (get the name?) invented the wrap around sandwich 30 years ago. Now, all other manufacturers have copied it...
...The reasoning you give is simply wrong. SS is a poor conductor, and makes poor cookware. Just the opposite of what you said happens.
If you think about it for a minute, you will see why. Poor conduction leads the spot above the flame to get hot, while the areas further away, stay relatively cool. Good conductivity allows that localized heat to spread out quickly, heating the cookware evenly.
I understand that, and if you read my post that's exactly what I was saying. I wasn't implying that a poor conductor immediately meant superior cookware, but I was (in a roundabout way, admittedly) trying to reconcile the point that both metals have their uses in cookware, esp. when used correctly (a la the all-clad sandwich design):
Aluminum is used for its conductivity and high specific heat, and stainless is used on the outside to start with an even heat (ref. my statement about uneven heating elements), and on the inside to prevent food contamination.
When their properties are exploited correctly, you end up with a product superior over either isolated material.
I understand that, and if you read my post that's exactly what I was saying. I wasn't implying that a poor conductor immediately meant superior cookware, but I was (in a roundabout way, admittedly) trying to reconcile the point that both metals have their uses in cookware, esp. when used correctly (a la the all-clad sandwich design):
Aluminum is used for its conductivity and high specific heat, and stainless is used on the outside to start with an even heat (ref. my statement about uneven heating elements), and on the inside to prevent food contamination.
When their properties are exploited correctly, you end up with a product superior over either isolated material.
The SS is simply used to provide a harder more resistant surface. It is very thin, and contributes little to cooking performance, at least, according to All-Clad.
It is also magnetic SS, and presents a flat surface to an induction cooktop, for which, of course, aluminum alone won't work. I have a single "burner" commercial induction cooktop, which works better to boil water than the 15,000 BTU gas burners on my range.
My SP 1.6Ghz G5 is still as quiet as the day I bought it. Though every few months or so, I blow the dust out of the system.
As for placement of the power supply, I'd venture to say it doesn't make much difference in the G5 design, as long as it were to stay isolated and had the same airflow as it currently does....
The ATX design doesn't *require* the power supply be in a certain position, it's just put there because that's the way PC cases are designed and have been for the past 20 years or so. You could really put it anywhere in the system you wanted to, it's just a matter of routing power cabling around the inside of the case.
Just to jump in here, Zang makes some important points worth looking at further.
1. The G5 design is attractive thermally in principle because of the division of different zones and the separate control of fan speed in those different zones. Pulling air from the front straight through out the back also makes very good sense.
2. There is no PC design that I have seen, custom or stock that has really come close to the design of the G5 in terms of setting up separate thermal zones and controlling those separately.
3. There are two caveats to 1. 2. above. 1. In real-world applications some people have not liked the acoustics of their dual-G5s. 2. If the separate thermal zones are separated mainly by aluminium, then the thermal zone theory gets a bit futzed because then heat from different thermal zones leak into each other. Worst case scenario with the heat leakage from thermal zones (from the zone to the aluminium to the air in the next zone) is like a PC box where it's one glob of hot air that your trying to vent out via a rear exhaust fan and the power supply exhaust fan.
4. My final year of college/ uni was a research project at a major bio research institute so I'm kinda hooked on data. It would be beautiful to see the fluid dynamics of G5s (eg. infrared video) compared to different PC cases along with acoustic measurements at different system loads. This would/ should be the next level for people like TomsHardware and AnandTech, moving beyond the "Is it possible to get 5fps more in FEAR" type 20+ page investigations.
5. Yes. A standard ATX motherboard in a standard PC technically does NOT require the power supply to be at the top. It's just there by convention. It *has* to be at the back though because otherwise if it is in front it is blowing it's own heat INTO the casing. So anyway, in a tower, the PCI/ PCIEx card slots are at the bottom back. So, the power supply will be at the top.
6. It is fascinating that in PC land there is a lot of motherboard-software interaction that deals with the fan speeds of chassis fans, cpu fan, and gpu fans. But again, based on the general design of the PC case, is still a big glob of hot air that you are trying to get out of the case in the best manner. Tidier cables is one, side intake fans and front intake fans are another design strategy, but really, nothing close to the theory of the PowerMac G5's thermal management.
I would venture that looking into the matter closer, there is still a lot of scope in PC tower case design for optimal airflow, acoustic management, and heat management. The PowerPC G5 has taken a bold move, and PeeCee land remains as it always is, slave to convention or the latest trends.
Remember now that Apple is mainly using Intel chipsets so for Towers to save R&D they could be going with quite standard motherboard designs. You can see in the iMac and laptops how they've been able to come up with innovative internal designs. Although success is mixed with if the "its still hot" reports for the MacBook/ MacBookPro are to be believed to a certain extent.
Anyway, Apple could also do the same to come up with a really interesting internal design for the Mac Pro, but that depends on Stevie J and gang and whether they want to spend R&D on that.
2. There is no PC design that I have seen, custom or stock that has really come close to the design of the G5 in terms of setting up separate thermal zones and controlling those separately. [/B]
Take a look at the Compaq W8000. It comes close on the theory. My SP700 as well, and it only has two large fans in the entire case. Both are older dual Xeon computers and both are designed to adequately cool 15kRPM hard drives as well. The power supplies are pretty nice that they have a fan on the PSU intake instead of the exhaust, the little noise made by that fan is very well diffused before it leaves the case.
Quote:
3. There are two caveats to 1. 2. above. 1. In real-world applications some people have not liked the acoustics of their dual-G5s. 2. If the separate thermal zones are separated mainly by aluminium, then the thermal zone theory gets a bit futzed because then heat from different thermal zones leak into each other. Worst case scenario with the heat leakage from thermal zones (from the zone to the aluminium to the air in the next zone) is like a PC box where it's one glob of hot air that your trying to vent out via a rear exhaust fan and the power supply exhaust fan.
I think the coolong in the dual G5s is more of an issue of using too many small fans. I think two large fans in push-pull like on my Compaq workstation is a lot less annoying than four small fans in push-pull because of the high pitch because the fans have to spin faster to move the same air.
Quote:
and PeeCee land remains as it always is, slave to convention or the latest trends.
Cool. Yeah fan size has a big influence on pitch and various acoustic characteristics of a tower.
"PeeCee land remains as it always is, slave to convention or the latest trends."
"That looks to be contradictory."
Hmmm... interesting isn't it? Nobody is going to come out with a motherboard which has the PCI/ PCIEx slots in a different location, yet at the same time everyone is rushing to get their boards "Core compatible". Herd mentality, I guess, is what I am trying to imply.
Hmmm... interesting isn't it? Nobody is going to come out with a motherboard which has the PCI/ PCIEx slots in a different location, yet at the same time everyone is rushing to get their boards "Core compatible". Herd mentality, I guess, is what I am trying to imply.
Why would they put their slots in a different location? Board makers are trying to sell interchangeable parts, not wind the clock to pre-Eli Whitney. There's nothing about the ATX format that prevents the application of the "zone" concept, my W8000 shows that pretty well. Unfortunately, the buyers often don't care, so it's not applied often enough due to small market demand.
When you have 2+ optical drives on a Mac the optical drive status shows up in the menu bar. The button ejects whatever has media in it starting with the top drive. If they're both empty it does the top. At least this is the way it worked in my old G4.
I have dual drives in my current G4 also. Not only do you get the drive option showing up in the status bar as mentioned in above post, you can also hold the option key down while hitting the eject key to eject the second drive. This way they can both be opened. Eject, top drive; Option+Eject lower drive.
I think the coolong in the dual G5s is more of an issue of using too many small fans. I think two large fans in push-pull like on my Compaq workstation is a lot less annoying than four small fans in push-pull because of the high pitch because the fans have to spin faster to move the same air.
Except that the G5's are pretty quiet. quieter than most every equivalent PC or workstation I've seen (or heard).
The fan speeds vary as well, so they usually aren't running at the highest speeds. Apple uses the number of fans it does because as we know, it cools each zone in the machine seperately. That contributes to the quietness.
Except that the G5's are pretty quiet. quieter than most every equivalent PC or workstation I've seen (or heard).
The fan speeds vary as well, so they usually aren't running at the highest speeds. Apple uses the number of fans it does because as we know, it cools each zone in the machine seperately. That contributes to the quietness.
Mel,
My Quad G5 fans at the rear of the case next to all the ports NEVER spin, even during the Apple Hardware Test. Yet, the CPU temps hover around 50 degree celcius. Does this seem normal to you?
Comments
Originally posted by JeffDM
Well, having a low frequency single chip is not much of a heat load. My W8000 has two Netburst 2.8GHz chips and it's noise is a lot more tolerable than my G5.
At any rate, I haven't seen much an argument why moving the power supply for the Mac Pros would be a bad thing.
I didn't know that my argument was about it being a "bad" thing. I just said it wasn't a very elegant or apple-like thing. There's already a well-designed heat removal system in the G5 case. Why futz with it when it's not necessary, and only adds to the rear panel clutter and cord knotting?
Originally posted by minderbinder
I don't think apple can do quad for $2K. But I think they can do conroe for $1500, maybe even less if they go minitower on the low end. Apple needs speed on the high end. On the low end, price is way more important than speed - people will complain more about a base model being too expensive than it not being fast enough.
Somewhere on this board, I worked out a way to get components for a 2 x 2.00 cost about $1700 w/ decent volume discounts. Apple picks a margin between 12.5 percent and 25 percent, and that computer costs between $2000 and $2200. It'd also be the best-selling workstation ever, because Dell's margins are off the charts in the workstation market.
I have to run, but I'll re-post that config tonight.
Originally posted by zang
I ceded in another comment that "conductor" was a poor choice of words on my part, when I meant to say something along the lines of thermal retention.
Aluminum will heat up very quickly, but it cools down just as fast. That's why it's used a lot in bakeware rather than cookware -- where most times it's in a situation where there's surrounding or convection heat and it's just used to hold something or form a shape, as opposed to cooking it.
That's not correct.
Aluminum is used in cookware all of the time. It's used by itself, and it's used in conjunction with stainless steel, for protection.
The fact that aluminum heats up quickly means it is a good conductor as well. Thermal and electrical conductivity go hand in hand.
Aluminum, as a good conductor, allows the heat to quickly spread to the rest of the piece when one part is heated.
The reason why baking pans, aluminum foil, and heatsinks cool down quickly is because the metal is thin for the purpose. When metal is thin, there is is a high ratio of surface area to volume. That allows the heat to escape quickly. That will occur with any metal that is uniformly heated.
By the way, being a poor conductor does not mean that something is an insulator.
Glass is not a poor conductor, it is an insulator. Lead is not an insulator, it is a poor conductor.
Originally posted by melgross
Aluminum is used in cookware all of the time. It's used by itself, and it's used in conjunction with stainless steel, for protection.
Protection from what? Aluminum and aluminum core cookware is aimed at the consumer market because it doesn't tarnish, it heats up quickly and it's lightweight. It is however, something you will rarely ever see a professional chef use on a cooktop. Anyone fresh out of culinary school will tell you that. I dare you to find me a professional chef who does use solid aluminum pans.
Aluminum, as a good conductor, allows the heat to quickly spread to the rest of the piece when one part is heated.
If something conducts temperature change well, it works both directions. If it heats up fast, it will cool down fast. Aluminum doesn't break these rules of thermodynamics. It will not have the same kind of uniform temperature the way that Iron, Steel, Copper or other metals have.
The reason why baking pans, aluminum foil, and heatsinks cool down quickly is because the metal is thin for the purpose. When metal is thin, there is is a high ratio of surface area to volume. That allows the heat to escape quickly. That will occur with any metal that is uniformly heated.
And "uniformly heated" is debatable. It's much harder to get an accurate uniform heating of an aluminum pan. Aluminum does not retain heat as well as other metals; that's why it's used in heatsinks and the scourge of professional chefs.
By the way, being a poor conductor does not mean that something is an insulator.
I did not say it was an insulator.
Might as well get some facts on the table with a link to some actual thermal conductivity with a little information even on cooking pot design and why a copper core can be used between stainless plates for a pot.
http://hypertextbook.com/physics/thermal/conduction/
I would bet that there are professionals who use aluminum as this is the primary metal for Calphalon. (It is anodized to provide a protective coating.) Aluminum is horrible with the acidity of many foods and should never be used with tomato sauces.
Now about the thermal design of the G5. I think it is great that Apple actually took the time to design a case to compensate for the heat load of the G5. My early Dual 2 rarely gets loud in summer and is even quieter in Winter when the house is cooler. I will guess that the Quads really benefit from the segregation and fan speed control.
It will be interesting to see what is done with the new chips and the 'lower' thermal requirements. I would love to see high performance chips in the another passively cooled 'cube' / original mac design. Will it ever happen again?
Originally posted by zang
[B]Protection from what? Aluminum and aluminum core cookware is aimed at the consumer market because it doesn't tarnish, it heats up quickly and it's lightweight. It is however, something you will rarely ever see a professional chef use on a cooktop. Anyone fresh out of culinary school will tell you that. I dare you to find me a professional chef who does use solid aluminum pans.
My oh my, you don't know much about cooking, do you?
Only the cheapest aluminum cookware is plain finish. Better quality mdels are anodized. Most high quality models, such as the All-Clad I have has a SS outer shell, a sandwitch of aluminum Aluminum, and an interior made up of SS again. Food acid, esp at high temps corrods aluminum, which is not considered to be healthy.
http://206.210.90.92/ (All-Clad)
Viking, Kitchenaid, etc, all have similar models.
The All-Clad is the most popular line of cookware in restaurants.
Copper is used on the most expensive models, but has not been shown to be better. Look to the reviews of pro level cookware in Cook's Illustrated, Fine Cooking, and elseware.
Please don't make things up. People here know too much.
If something conducts temperature change well, it works both directions. If it heats up fast, it will cool down fast. Aluminum doesn't break these rules of thermodynamics. It will not have the same kind of uniform temperature the way that Iron, Steel, Copper or other metals have.
And "uniformly heated" is debatable. It's much harder to get an accurate uniform heating of an aluminum pan. Aluminum does not retain heat as well as other metals; that's why it's used in heatsinks and the scourge of professional chefs.
It's used because of the reasons I already gave.
I did not say it was an insulator.
Yes, I know, Jeff said it. I mentioned it in that post because we were talking about that subject.
Slightly poorer conductors will spread hotspots out more, using this same reasoning.
Originally posted by benzene
The reason I've always heard given for the avoidance of aluminum in professional cookware is that it's too good of a conductor, and that any hotspots in your burner/heating element translate into local hotspots in your cookware.
Slightly poorer conductors will spread hotspots out more, using this same reasoning.
That's why All-Clad (get the name?) invented the wrap around sandwich 30 years ago. Now, all other manufacturers have copied it.
It also depends upon the design itself. Good designs, such as All-Clad's, work very well. Some others, don't.
The reasoning you give is simply wrong. SS is a poor conductor, and makes poor cookware. Just the opposite of what you said happens.
If you think about it for a minute, you will see why. Poor conduction leads the spot above the flame to get hot, while the areas further away, stay relatively cool. Good conductivity allows that localized heat to spread out quickly, heating the cookware evenly.
The proof is in the pudding, so to speak.
Originally posted by melgross
That's why All-Clad (get the name?) invented the wrap around sandwich 30 years ago. Now, all other manufacturers have copied it...
...The reasoning you give is simply wrong. SS is a poor conductor, and makes poor cookware. Just the opposite of what you said happens.
If you think about it for a minute, you will see why. Poor conduction leads the spot above the flame to get hot, while the areas further away, stay relatively cool. Good conductivity allows that localized heat to spread out quickly, heating the cookware evenly.
I understand that, and if you read my post that's exactly what I was saying. I wasn't implying that a poor conductor immediately meant superior cookware, but I was (in a roundabout way, admittedly) trying to reconcile the point that both metals have their uses in cookware, esp. when used correctly (a la the all-clad sandwich design):
Aluminum is used for its conductivity and high specific heat, and stainless is used on the outside to start with an even heat (ref. my statement about uneven heating elements), and on the inside to prevent food contamination.
When their properties are exploited correctly, you end up with a product superior over either isolated material.
table of common metal specific heat capacities
Originally posted by benzene
I understand that, and if you read my post that's exactly what I was saying. I wasn't implying that a poor conductor immediately meant superior cookware, but I was (in a roundabout way, admittedly) trying to reconcile the point that both metals have their uses in cookware, esp. when used correctly (a la the all-clad sandwich design):
Aluminum is used for its conductivity and high specific heat, and stainless is used on the outside to start with an even heat (ref. my statement about uneven heating elements), and on the inside to prevent food contamination.
When their properties are exploited correctly, you end up with a product superior over either isolated material.
table of common metal specific heat capacities
The SS is simply used to provide a harder more resistant surface. It is very thin, and contributes little to cooking performance, at least, according to All-Clad.
It is also magnetic SS, and presents a flat surface to an induction cooktop, for which, of course, aluminum alone won't work. I have a single "burner" commercial induction cooktop, which works better to boil water than the 15,000 BTU gas burners on my range.
My SP 1.6Ghz G5 is still as quiet as the day I bought it. Though every few months or so, I blow the dust out of the system.
As for placement of the power supply, I'd venture to say it doesn't make much difference in the G5 design, as long as it were to stay isolated and had the same airflow as it currently does....
The ATX design doesn't *require* the power supply be in a certain position, it's just put there because that's the way PC cases are designed and have been for the past 20 years or so. You could really put it anywhere in the system you wanted to, it's just a matter of routing power cabling around the inside of the case.
Just to jump in here, Zang makes some important points worth looking at further.
1. The G5 design is attractive thermally in principle because of the division of different zones and the separate control of fan speed in those different zones. Pulling air from the front straight through out the back also makes very good sense.
2. There is no PC design that I have seen, custom or stock that has really come close to the design of the G5 in terms of setting up separate thermal zones and controlling those separately.
3. There are two caveats to 1. 2. above. 1. In real-world applications some people have not liked the acoustics of their dual-G5s. 2. If the separate thermal zones are separated mainly by aluminium, then the thermal zone theory gets a bit futzed because then heat from different thermal zones leak into each other. Worst case scenario with the heat leakage from thermal zones (from the zone to the aluminium to the air in the next zone) is like a PC box where it's one glob of hot air that your trying to vent out via a rear exhaust fan and the power supply exhaust fan.
4. My final year of college/ uni was a research project at a major bio research institute so I'm kinda hooked on data. It would be beautiful to see the fluid dynamics of G5s (eg. infrared video) compared to different PC cases along with acoustic measurements at different system loads. This would/ should be the next level for people like TomsHardware and AnandTech, moving beyond the "Is it possible to get 5fps more in FEAR" type 20+ page investigations.
5. Yes. A standard ATX motherboard in a standard PC technically does NOT require the power supply to be at the top. It's just there by convention. It *has* to be at the back though because otherwise if it is in front it is blowing it's own heat INTO the casing. So anyway, in a tower, the PCI/ PCIEx card slots are at the bottom back. So, the power supply will be at the top.
6. It is fascinating that in PC land there is a lot of motherboard-software interaction that deals with the fan speeds of chassis fans, cpu fan, and gpu fans. But again, based on the general design of the PC case, is still a big glob of hot air that you are trying to get out of the case in the best manner. Tidier cables is one, side intake fans and front intake fans are another design strategy, but really, nothing close to the theory of the PowerMac G5's thermal management.
I would venture that looking into the matter closer, there is still a lot of scope in PC tower case design for optimal airflow, acoustic management, and heat management. The PowerPC G5 has taken a bold move, and PeeCee land remains as it always is, slave to convention or the latest trends.
Remember now that Apple is mainly using Intel chipsets so for Towers to save R&D they could be going with quite standard motherboard designs. You can see in the iMac and laptops how they've been able to come up with innovative internal designs. Although success is mixed with if the "its still hot" reports for the MacBook/ MacBookPro are to be believed to a certain extent.
Anyway, Apple could also do the same to come up with a really interesting internal design for the Mac Pro, but that depends on Stevie J and gang and whether they want to spend R&D on that.
Originally posted by melgross
I have a single "burner" commercial induction cooktop, which works better to boil water than the 15,000 BTU gas burners on my range.
How does that compare to a Macbook?
Originally posted by sunilraman
2. There is no PC design that I have seen, custom or stock that has really come close to the design of the G5 in terms of setting up separate thermal zones and controlling those separately. [/B]
Take a look at the Compaq W8000. It comes close on the theory. My SP700 as well, and it only has two large fans in the entire case. Both are older dual Xeon computers and both are designed to adequately cool 15kRPM hard drives as well. The power supplies are pretty nice that they have a fan on the PSU intake instead of the exhaust, the little noise made by that fan is very well diffused before it leaves the case.
Quote:
3. There are two caveats to 1. 2. above. 1. In real-world applications some people have not liked the acoustics of their dual-G5s. 2. If the separate thermal zones are separated mainly by aluminium, then the thermal zone theory gets a bit futzed because then heat from different thermal zones leak into each other. Worst case scenario with the heat leakage from thermal zones (from the zone to the aluminium to the air in the next zone) is like a PC box where it's one glob of hot air that your trying to vent out via a rear exhaust fan and the power supply exhaust fan.
I think the coolong in the dual G5s is more of an issue of using too many small fans. I think two large fans in push-pull like on my Compaq workstation is a lot less annoying than four small fans in push-pull because of the high pitch because the fans have to spin faster to move the same air.
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and PeeCee land remains as it always is, slave to convention or the latest trends.
That looks to be contradictory.
"PeeCee land remains as it always is, slave to convention or the latest trends."
"That looks to be contradictory."
Hmmm... interesting isn't it? Nobody is going to come out with a motherboard which has the PCI/ PCIEx slots in a different location, yet at the same time everyone is rushing to get their boards "Core compatible". Herd mentality, I guess, is what I am trying to imply.
Originally posted by sunilraman
Hmmm... interesting isn't it? Nobody is going to come out with a motherboard which has the PCI/ PCIEx slots in a different location, yet at the same time everyone is rushing to get their boards "Core compatible". Herd mentality, I guess, is what I am trying to imply.
Why would they put their slots in a different location? Board makers are trying to sell interchangeable parts, not wind the clock to pre-Eli Whitney. There's nothing about the ATX format that prevents the application of the "zone" concept, my W8000 shows that pretty well. Unfortunately, the buyers often don't care, so it's not applied often enough due to small market demand.
Originally posted by york2600
When you have 2+ optical drives on a Mac the optical drive status shows up in the menu bar. The button ejects whatever has media in it starting with the top drive. If they're both empty it does the top. At least this is the way it worked in my old G4.
I have dual drives in my current G4 also. Not only do you get the drive option showing up in the status bar as mentioned in above post, you can also hold the option key down while hitting the eject key to eject the second drive. This way they can both be opened. Eject, top drive; Option+Eject lower drive.
Originally posted by backtomac
How does that compare to a Macbook?
It's definitely hotter. But, when it gets going at the highest "speed", it's really cooking!
Originally posted by JeffDM
I think the coolong in the dual G5s is more of an issue of using too many small fans. I think two large fans in push-pull like on my Compaq workstation is a lot less annoying than four small fans in push-pull because of the high pitch because the fans have to spin faster to move the same air.
Except that the G5's are pretty quiet. quieter than most every equivalent PC or workstation I've seen (or heard).
The fan speeds vary as well, so they usually aren't running at the highest speeds. Apple uses the number of fans it does because as we know, it cools each zone in the machine seperately. That contributes to the quietness.
Originally posted by melgross
Except that the G5's are pretty quiet. quieter than most every equivalent PC or workstation I've seen (or heard).
The fan speeds vary as well, so they usually aren't running at the highest speeds. Apple uses the number of fans it does because as we know, it cools each zone in the machine seperately. That contributes to the quietness.
Mel,
My Quad G5 fans at the rear of the case next to all the ports NEVER spin, even during the Apple Hardware Test. Yet, the CPU temps hover around 50 degree celcius. Does this seem normal to you?
Thanks, Billy