Dual Processor PowerBooks??
The introduction of the Xserve showed us apple can fit dual G4 processors in a 1.75" space. I know that's not 1" like the PowerBook. But hey, It could be possible. Just think, the first computer company to ship Dual processor Laptops. That would really put apples popularity skyrocketing. The only con about dual processor laptops is heat and power consumption.
I wish I may, I wish I might, I think i see a dual processor laptop in my sight.
I hope!!!
I wish I may, I wish I might, I think i see a dual processor laptop in my sight.
I hope!!!
Comments
Still, an interesting idea. Would be neat if they somehow made two processors that shared some cache or something(?)
Have you seen (or heard) those fans in the Xserve, though?
Man, I'd fall over laughing if I even heard a PowerBook revving up like that!
That decision really shouldnt be to hard to make. Performace before noise level.
There is a market for heavier and more powerful portables (you see them on the PC side), and it would be nice if apple would make one.
O' what I would do for a dual 1Ghz PowerBook with a Superdrive...
I like your thinking though
<strong>That decision really shouldnt be to hard to make. Performace before noise level.</strong><hr></blockquote>
Oh no?
Well, in a portable which can't be banished to the closet, I choose noise level before performance.
But, technologies to make a dual/psuedo-dual TiBook do exist. IBM wants to use a .13u SOI low-K dielectric G3 in its upcoming Sahara. 3.6Watts power consumption at 800Mhz. That is very, very, very good.
Mot made an 800Mhz G4 useable in a TiBook by just adding SOI. Apple put some agressive heat sink and venting tech on it, and presto, it not only runs in the TiBook, it runs cooler than the previous generation non-SOI 667. Not Bad, but there's at least 2 technologies that could be thrown at this current G4 to considerably lower it's heat and power drain. Firstly, and if not overdue already, is a die-shrink down to .13u. Secondly, the addition of a low-K dielectric fab technique might provide a similar boost in efficiency as SOI did. Those two technologies could cut a G4's heat and power drain down to half their current levels, maybe more.
Chips up to twice as hot as a single G4 are going into laptops, it is possible to adress the heat concerns through some industrial design work, as Apple has demonstrated, though perhaps it is not possible to do much about power drain without speed stepping the chips.
You could speed step the machine by shutting down one proc when on battery power and perhaps save some space/energy by having the procs share one large cache. Maybe 2MB used by both procs simultaneously (I think MERSI supports this). when one G4 shuts off, the other still has access to the full 2MB, when both are on, they share access to it. Some intelligent power control logic could deep sleep the second even during plugged-in operation if the processor load is not sufficient to warrant DP operation -- in the interests of heat dissapation.
BUT,
The question remains, if a fab process existed to effectively halve a CPU's power-consumption/heat dissapation, then that same technology could be used to double that same CPU's clock speed and maintaing current heat/power drain numbers.
Which is better? Probably a single faster chip for reasons of manufacturing complexity and space. It could be a seriously effective marketing coup to have the only DP notebook in existence available only from Apple, but it might also be equally effective to have one of the single fastest chips on the market in a notebook and use the money saved over a DP design to add more storage, video and audio features.
I wonder if they haven't at least looked at it? Just as a design exercise, with no real intention of actually making it, just to see if it could be done, and what would be learned along the way?
If Apple made the current battery bay a polymer battery, and made the whole bottom of the machine another half a cnetimeter thicker, then you could achieve five hours of performance with a dual Ghz powerbook. I'm just pulling nmumber s oout of my ASs.
Secondly, the processor itself is only barely a mm thick, and multiple processors are put side to side, not stacked, so it is the width that is relevant for this, not height, and you'll notice the XServe is at least twice the width and length of a PowerBook.
Thirdly, the power consumption of the processor and the heat produced (which are of course related) are the limiting factors for PowerBook usage, the size is trivial, you could fit two in the PCMCIA slot for goodness sake if they didn't have to be cooled.
I'm all for producing a PB with dual processors. It could shut off one processor when not in use, or by user request, or when not plugged in. But price, heat and battery life are what's holding this back, not size. And the properties of the XServe are utterly irrelevant, it's size and shape is entirely dictated by the need for multiple drive bays and rack mount dimensions, not processor volume.
Socrates
But if you look inside the tiBook, you'll realize that there isn't really any space for a 2nd proc. If the whole mobo were made into an IC. . . .
<strong>Would you rather have a laptop with loud fans, but was a tottal screamer in performace. Or a computer that while quite, was nearly half as slow.
That decision really shouldnt be to hard to make. Performace before noise level.</strong><hr></blockquote>
LOL
simple solution.... get the first CPU to run fast enough so you don't need silly solutions like a dual CPU lappie ... <img src="graemlins/smokin.gif" border="0" alt="[Chilling]" />
We will never see x2 G4 PB - the design is just wrong for that, the heat, size, bettery life, noize, space , rediculousness.....
It would probaly be easier to get faster G4 then to engineer a dual CPU solution for the PB.
With two proccessors you can take advantage of programs which use multiple processors.
What apple engineers could come up with is a solution. When pluged into a wall Mac OS X could turn keep both processors running. When on battery power it could turn one off. With this there is no worry about battery or heat. Apple could develop a special TI pad to put underneath the Powerbook to remove extra amount of heat faster. Two processors might even use less energy than one. If one has to do all the work it will use a lot of power to run at full speed. If two can split the job not running at full power, the power intake might even be the same.
Sounds like a cool idea to me. It is kind of like the big Mercedes V12 engines in the S-Class etc. They can turn off half the engine if you are going slowly,and you don't even notice the difference. It would be good if processors could be turned and and off like that. Just run one if word processing, but turn them both on if gaming or doing graphics work. Unfortunately this is all just a bit of a nice dream, and even if it did ever happen, it would only ever be in top range models. Sounds cool though, novelty value as well!
would it really kill you? all altivec optimized would go to the G4, the rest to the G3.
(although at this stage that might leave your G3 waiting.....)
<strong>
Sounds like a cool idea to me. It is kind of like the big Mercedes V12 engines in the S-Class etc. They can turn off half the engine if you are going slowly,and you don't even notice the difference. It would be good if processors could be turned and and off like that. Just run one if word processing, but turn them both on if gaming or doing graphics work. Unfortunately this is all just a bit of a nice dream, and even if it did ever happen, it would only ever be in top range models. Sounds cool though, novelty value as well!</strong><hr></blockquote>
As a matter of fact, this is sort of how it works today. From <a href="http://developer.apple.com/techpubs/hardware/Developer_Notes/Macintosh_CPUs-G4/PowerBook_G4/1Introduction/Power_Saving_Features.html" target="_blank">the PB tech docs</a>:
[quote]Operating Modes
The power management protocols on the PowerBook G4 computer support two power-saving modes: Idle and Sleep.
Idle: The system is idling with the main processor stopped in Nap mode. All clocks are running; the system can return to running code within a few nanoseconds. Cache coherency is maintained in this level of idle.
Sleep: The system is completely shut down, with only the DRAM state preserved for quick recovery. All processors are powered off with their state preserved in DRAM. All clocks in the system are suspended except for the 32.768 kHz timebase crystal on the PMU99 IC.
The computer automatically enters Idle mode after several seconds of inactivity. If the computer is attached to a network, it is able to respond to service requests and other events directed to the computer while it is in Idle mode.
While it is connected to an AC power supply, the computer can also respond to network activity when it is in Sleep mode. The user can enable this feature by selecting Wake-on-LAN in the Energy Saver control panel.
In Sleep mode, the computer consumes less than 1 watt of power. That allows it to meet the Energy Star power-saving standard.
<hr></blockquote>
Bye,
RazzFazz
[ 05-28-2002: Message edited by: RazzFazz ]</p>
Lithium polymer batteries
that new type of thermoelectric junction.. wazzit called... Thermal Breeze? i forget... it was on this forum or MacNN a while ago
The junction tech is thus - electrons are not particles - they are waves. So, an electron's position is not definite. A quickly moving electron is spread out over a large volume of possible positions. Hot substances have both vibrational energy and electrons jumping out further from the nucleus.
If you put two surfaces very close together, it's possible to get the fast electrons to jump the gap.
The problem was, it was impossible to get two centimer-suzed surfaces within say a micron of eachother without them touching at a couple of points. The company that developed the new thermoelectric cooler fgigured out how to do that and is making them right now.