I was running a host with a Radeon HD5770, mostly for BOINC (Astropulse with S@H). So far so good.
Now I've put another graphics card, a NVIDIA GT240 into that host (to crunch MB with S@H).
My motherboard has two PCIe 2.0 slots (one with 16, the other only with 4 lanes).
As long as have the HD5770 in the first PCIe slot (with 16 lanes), and the GT240 in the other (with 4 lanes) all works fine.
But for cooling purposes it would be better to swith the cards.
Unfortunately this does not work.
When I put the HD5770 in the PCIe slot with 4 lanes, and the GT240 in the slot with 16 lanes, Catalyst driver reports "no ATI hardware found" (or something like).
This is strange, because in Windows device manager I can see both cards.
When I put the HD5770 in the PCIe slot with 4 lanes, and remove the GT240, Catalyst correctly detects the card?!?!
What to do?