2xGPU

[zygo]

I have a x1900 installed in my Mac Pro and want to add more monitors. I've heard there may be problems with putting a 7300 in there with it?

Is it possible to run 2 x1900's? don't they need double bay PCI-e?


Also how does the system allocate things to the GPU? For example I want to run an a/v performance using Ableton and VDMX running dual monitors(1 for ableton, 1 for VDMX/Module8) with dual projection. I also occassionally will want to run 1monitor with 3 projectors.

Would it be possible for the system to run off the 7300 and the projectors off the x1900 giving the most power to the visuals (i'm assuming that way would give visuals the most power?)?

 

[Mackilroy]

It is possible to run two x1900s simultaneously – there's an article somewhere about it, but I don't have time to look it up right now. As for division of resources when you have multiple monitors, well, say you have two monitors and one graphics card with 512 MiB of RAM – then one monitor will 256, and the other will get the other 256.

For the last question – I would imagine so, I've seen it done with only one graphics card and no reason why it can't be done with two. Could be wrong, though.

 

[Celeron]

I think its possible. If I'm not mistaken both cards will running at PCIx8 instead of PCIx16 (with just one card). I think this makes only a negligible difference in performance.

 

[zygo]

But would still be way more powerful than a 7300?

One thing seriously putting me off 2xATi is losing a PCI slot.

Are the newer cards (if they ever come to mac) going to be compatible with the current Mac Pro and are they likely to be double slot size? I'm wondering if I'd be better off waiting-maybe getting a 512 that fits in 1slot?

 

[jasonvp]

I'm wondering if I'd be better off waiting-maybe getting a 512 that fits in 1slot?

As long as GPUs are running as hot as they are, they're going to need massive heat sinks and their own fans. And that's why they're taking up 2 slots.

The only real way to go single-slot with those particular cars is to liquid cool them. I've done that on my gaming PC with my two nVidia 7900GTXs. It keeps them nice and cool, and the box nice and quiet. And I don't have to donate 4 slots (2 slots x 2 cards) to video.

In the future, GPUs may start to benefit from some of the power management that Intel and AMD have worked in with their CPUs. And then they won't require the massive heat sinks and fans. Until then, they're 2-slot monsters (and very loud ones at that).

jas