Double 8800GT in 2008 Mac Pro

[peskaa]

I have an 8-core 2.8 Mac Pro, early 2008 model. I bought it from Apple with an 8800GT in the first slot, but I'm currently looking at adding a second card, which is where I get incredibly confused.

I would like to run a pair of 8800GTs ideally - I know they won't run in SLi, but having the VRAM will be a help. Now, the 300w limit in the PCIe bay worries me - will a pair of 8800GTs go over this? The Genius Bar at Regent Street were about as useful as a snowball in hell at answering, babbling on about warranty crap rather than answering the question.

I've heard that an 8800GT and a 2600HD work, but I'd prefer not to go down the different cards route - if only because Windows (vista64 to be exact) will most likely complain.

 

[Mackilroy]

You certainly can use two 8800 GTs in the 2008 Mac Pros. I don't recall the exact power limit, but I've heard of other people doing so.

 

[Siron]

Why would you want another 8800 except to run four monitors! There is no way to share the GPU load across two cards. The only reason Apple let you configure more cards is to run more monitors (the 8800 can run two).
Alan

 

[Tallest Skil]

You cannot combine processing power across cards in any way in OS X. The only reason to have two cards is to run multiple displays.

For the record, I will have two 9800 GT in my Nehalem Mac Pro to run one display off of each. It's almost beating the system.

 

[peskaa]

You cannot combine processing power across cards in any way in OS X. The only reason to have two cards is to run multiple displays.

I know this - I'm intending to use the current 23" ACDs off one card, and then a 40" HDTV off the second, with an expansion to a third 23" ACD later. The 8800GTs have a decent chunk of VRAM, which in turn makes them more future proof.

 

[Tallest Skil]

Ah. Good. You understand. Having said that, it's possible and doesn't exceed the power draw. There's a member of MacRumors that runs two 8800 GT in his Mac Pro already.

The Apple guys were beating around the bush because they were too afraid to try it.

 

[fergusonbk]

on the reals

tallest skill I think I speak for everyone hear when I say : shutup. Tired of hearing about your nehalem **** go brain yourself.

 

[madboom]

I have an 8-core 2.8 Mac Pro, early 2008 model. I bought it from Apple with an 8800GT in the first slot, but I'm currently looking at adding a second card, which is where I get incredibly confused.

I would like to run a pair of 8800GTs ideally - I know they won't run in SLi, but having the VRAM will be a help. Now, the 300w limit in the PCIe bay worries me - will a pair of 8800GTs go over this? The Genius Bar at Regent Street were about as useful as a snowball in hell at answering, babbling on about warranty crap rather than answering the question.

I've heard that an 8800GT and a 2600HD work, but I'd prefer not to go down the different cards route - if only because Windows (vista64 to be exact) will most likely complain.

Yes beware the different card route, it has not been a great experience for me. And as you already know the Genius Bar isn't always quite as top notch as we might like them to be.