DDR coming soon?
Last year, after the new powermacs were introduced at MWNY, I noticed a reference to DDR-SDRAM on the Apple store web site. It was when you clicked continue 2 times and got to the last page with the summary. This is where it mentioned DDR-SDRAM. I took a screen shot so I would have a record of the price.
I'm wondering if they were going to use DDR but changed their minds at the last minute and the person in charge of updating the store forgot to remove it.
If I knew how to paste the picture in with this post, I would.
- Mark
I'm wondering if they were going to use DDR but changed their minds at the last minute and the person in charge of updating the store forgot to remove it.
If I knew how to paste the picture in with this post, I would.
- Mark
Comments
Anyway I was just reading my new macaddict(March/02) and got to the ads. OWC has is advertising:
*NEW* DDR MEMORY
Double Data Rate Rame for the 2002 Apple PowerMacs
128MB.....$CALL
256MB.....$CALL
512MB.....$CALL
Just thought it was an interesting little tidbit of info. I know it's probably just speculation on their part that we will finally get better subsytems, but it's still interesting none the less.
That would have been cool! huh, huh, he he , huh, huh, yeah, ddr RAM rules!
Of course it's only a L3 cache but with a memory bandwitch up to 4 GByte per second.
I think that we will never see DDR ram mobo in a G4 for this reason.
Because the architecture of the memory of the new G4 is different of an architecture of Athlon or P4, it has a very efficient L3 cache system, that can make useless the use of a DDR memory instead SDRAM memory.
I think it will be of the greatest interest to see comparision between a G4 800 with L3 cache with the new G4 without L3 cache. Unfortunately, the too chips are slighty different and the old G4 800 has the old version of the L3 cache.
Is there anyone on AI ready to bet with me that the L3 cache brings the same amount of extra performance than the use of DDR ram ?
I saw on another thread that the Top of the line GeForce 4 has a 660 Mhz memory clock. Why isn't this memory clock speed available for main system memory? If you could run the mmory bus at 600 Mhz it seems like you would oupace any current DDR solution.
<strong>Stupid question
I saw on another thread that the Top of the line GeForce 4 has a 660 Mhz memory clock. Why isn't this memory clock speed available for main system memory? If you could run the mmory bus at 600 Mhz it seems like you would oupace any current DDR solution.</strong><hr></blockquote>
are you sure to be in the right topic
<a href="http://www.theinquirer.net/01020204.htm" target="_blank">DDR RAM</a>
<strong>
Because the architecture of the memory of the new G4 is different of an architecture of Athlon or P4, it has a very efficient L3 cache system, that can make useless the use of a DDR memory instead SDRAM memory.
(...)
Is there anyone on AI ready to bet with me that the L3 cache brings the same amount of extra performance than the use of DDR ram ?</strong><hr></blockquote>
This is wishful thinking.
An L3 cache is only ever of any use with data that get's used more than once, which specifically is not the case with most multimedia data.
There are cases where L3 + SDR is faster than DDR alone, but there are a lot of others where this is not so.
And, given OS X's memory requirements, it would probably fall into the second category unfortunately.
Bye,
RazzFazz
<strong>Stupid question
I saw on another thread that the Top of the line GeForce 4 has a 660 Mhz memory clock. Why isn't this memory clock speed available for main system memory? If you could run the mmory bus at 600 Mhz it seems like you would oupace any current DDR solution.</strong><hr></blockquote>
For one, this most definitely is DDR memory at 330MHz (and they just give the "effective" MHz number, as everyone seems to do). Furthermore, frequencies as high as those rule out the use of socketed memory modules (i.e. the chips have to be soldered directly onto the board, with minimal circuit lengths). This is kinda undesirable for main memory, since RAM is probably most frequently upgraded.
Bye,
RazzFazz
<strong>Is there anyone on AI ready to bet with me that the L3 cache brings the same amount of extra performance than the use of DDR ram ?</strong><hr></blockquote>
It depends on what you're doing, powerdoc. If you have a program that has to touch each pixel of a 100 megabyte image or movie exactly once, then your vaunted L3 cache will do nothing for you. On the other hand, if you have a 2 megabyte image that you will be touching repeatedly, then it will make a much bigger difference than DDR.
I agree that having a faster L3 cache makes a big difference, but that doesn't mean that DDR RAM won't deliver a performance benefit as well. Consider what happens when the L3 cache fills up with modified data and then you need to make room for a new piece of data... some old data from the cache must be written back to the main memory. With DDR RAM this takes half as long.
<strong>Stupid question
I saw on another thread that the Top of the line GeForce 4 has a 660 Mhz memory clock. Why isn't this memory clock speed available for main system memory? If you could run the mmory bus at 600 Mhz it seems like you would oupace any current DDR solution.</strong><hr></blockquote>
The problem is that the current G4's bus is limited to 64-bits x 133 MHz, non-double pumped. This means that super fast memory couldn't get data into the processor any faster than 133 MHz SDRAM.
<strong>Interesting article on the future of PC2700 DDR memory.
<a href="http://www.theinquirer.net/01020204.htm" target="_blank">DDR RAM</a></strong><hr></blockquote>
Interesting blurb, and it should demonstrate why we'll probably never see a PowerMac of any sort with 333 MHz DDR RAM. The next widely available standard is probably going to be DDR-II, and Apple will likely stick to the widely available standards.
<strong>I think Apple will skip DDR entirely and go to the next best thing for the PowerMacs. Just speculation, I know nothing, but Apple likes to adopt things before PCs do (USB, Firewire, SuperDrive, etc.)., not after ("We missed the boat entirely" (refering to optical drives). The last thing they are going to want to do is go and say "Hey, we finally got there too!".</strong><hr></blockquote>
Possibly -- DDR-II is coming. The only complication is that memory is expensive until it reaches widespread adoption, so this would cut into their margins.
"The DDR RAM myth: why two heads are better than one, and why a Powermac with sdRAM is actually3 times faster than a PC with ddr RAM. It's a myth that memory bandwidth or speed has any affect on system performance, what really matters is that powermacs use a special kind of RAM that is actually faster, because it has two brains instead of one brain. The RAM with the most brains is always the fastest".
he he, I like the two brains are better than one slogan, Apple should make a myth out of it.
<strong>Maybe Apple will stick with sdRAM far into the future,
"The DDR RAM myth: why two heads are better than one, and why a Powermac with sdRAM is actually3 times faster than a PC with ddr RAM. It's a myth that memory bandwidth or speed has any affect on system performance, what really matters is that powermacs use a special kind of RAM that is actually faster, because it has two brains instead of one brain. The RAM with the most brains is always the fastest".
he he, I like the two brains are better than one slogan, Apple should make a myth out of it.</strong><hr></blockquote>
Heh, where'd you get that crap? Its total bunk.
<strong>
Heh, where'd you get that crap? Its total bunk.</strong><hr></blockquote>
There's actually some truth to it - think memory bank interleaving.
Bye,
RazzFazz