Apple claims that its a hardware limitation - aka. theyve made it so the mobo wont address more than 8GB.
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Should I get 2x2.26 or Quad 2.93 Mac Pro?
- Thread starter Greenhoe
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Apple claims that its a hardware limitation - aka. theyve made it so the mobo wont address more than 8GB.
Do anyone know this - it sound like stupid if it should not accept more ram that 8GB. Im very close to get the Mac Pro 4 core but hesitate because of the ram limit - now it too expensive anyway and I dont really need more the 8 but in a years time it might be handy?
Until we get someone to test, it's just guesswork at this stage - but I would love to know.
IainH may be on the money - but as has been pointed out on other threads, with other machines, what Apple has said and what was possible were two different things.
Although Apple always said the non-SR C2D MacBooks could take a maximum of 2GB, you could install 4GB (but only 3.3GB was accessible by the machine). It was quite fun here on MacRumors, people quoting Apple's specs and arguing with people that had installed this, that it couldn't be done.
There were a lot of theories about this (e.g. Apple not wanting to confuse the consumer or worried that people were going to pay for RAM they couldn't actually use) - it did occur to me that Apple might have been using this a way of suggesting a larger differential between the MBPs, although it could gave been a combination of factors and this was just a 'bonus' for Apple.
I stressed 'might' as I've no evidence to support this.... I just have a base cynical mind! That said, I do think that the 8GB limit is going to help sway people opting for a octo machine instead...
*edit* Oops, sorry! IainH merely stated what Apple's line is, which I didn't reflect in my post.
While it has been mentioned by others, I want to emphasize that in my 'reading the tea leaves', these machines have been designed with Snow Leopard as the envisioned OS rather than Leopard.
While it will be great when things like Adobe CS are designed to specifically run on multiple cores, I expect that Snow will farm apps to their own cores thus making pretty much any app faster depending on the number of cores and the number of applications open. I'd wouldn't be surprised to find that memory management also has its own core.
Honestly, I'd wait until Snow Leopard before deciding if you don't know whether you want a 4-core or 8-core for best performance. Benchmarks and tests run under 10.5 may very well mislead in regards to how these machine will compare under 10.6.
While it will be great when things like Adobe CS are designed to specifically run on multiple cores, I expect that Snow will farm apps to their own cores thus making pretty much any app faster depending on the number of cores and the number of applications open. I'd wouldn't be surprised to find that memory management also has its own core.
Honestly, I'd wait until Snow Leopard before deciding if you don't know whether you want a 4-core or 8-core for best performance. Benchmarks and tests run under 10.5 may very well mislead in regards to how these machine will compare under 10.6.
We tested both the 2.26GHz octo-core and 2.93GHz quad-core Mac Pro using the 64-bit version of Cinebench. The 2.26 is faster.
Now, only some Photoshop filters are MP aware, so the benefit of the extra cores will depend on which ones you use. More important, though, is the memory. The octo-core 2.26 has more memory slots. You can expand up to 16GB vs only 8GB on the quad-core 2.93. It's possible that 4GB modules will work in the quad-core but they are going to cost you $1200 per module.
Memory is key because, Photoshop is able to use more than the 3GB memory cache defined in preferences. If you overflow that and there is memory to spare, OS X will allocate unused memory as a virtual scratch volume. Now maybe 8GB is enough for your use if you edit smaller files with few layers. But if you are editing RAW photos with lots of layers and lots of history states, you can use up the 8GB in a hurry.
I feel like the 2009 2.9 quad with 8gb would be a pretty nice and fast box. I have a 2008 quad 3.2 and would love to have the faster memory architecture that the 2009 has, but it seems that I would have to go the whole quad 2.9 overly expensive route to get there. On normal stuff though, I wonder if I would notice a performance increase at all with a quad 2.9 2009 vs my octo 3.2, both using 8gb ram? I'm thinking probably on non intensive stuff that doesn't need 8 cores, but probably not by any significant amount. We need an complete comparison chart to all of the various 2008/2009 combinations for this sort of thing.