May 11, 2011
I’ve tested today a system with one nvidia (8800gt) and one ati (4850) card and how this combination behaves in osx and win7.
win drivers – catalyst 11.4 and geforce 270.xx
osx drivers – from latest imac update.
first variant: nvidia – first card (POSTed by bios), ati – second
win7: gpu-z cant show proper info about ati card until I plug a display connector to it, then I still cant use 3d renderer of ati card, only 8800gt renderer available to opengl apps. Aida64 says only one d3d/opengl renderer available. this combo leads to a lot of instabilities of Win7. I cant run any directcompute/opencl app on 4850, system freezes.
MacOSX Snow Leopard: All works fine. Can use both renderers (8800gt and 4850) with any screen combination (for example app rendering on 4850 can be shown on screen driven by 8800gt, this leads to some fps drops, cuz system needs to copy rendered image from one card to another, but fps still at acceptable level). Can use opencl engine of any card at any time, and both in time. No problems except one – when running luxmark using both opencl devices (it cant use jsut one), the gui is very slow.
second: 4850 is first card, 8800gt is second.
Win7: even more freezes, durring running gpuz.
OSX: 8800gt wasn’t initialized by drivers, so drivers doesnt see any outputs on it, any renderers/opencl devices. 4850 works fine.