5870 CrossFire Issues
I just bought a second 5870 (Gigabyte Eyefinity 6 edition). I installed it in CrossFire with my other 5870 (Diamond branded reference design). I'm running Catalyst 11.3 (freshly reinstalled) and have the CrossFire bridge in place. The Catalyst Control Center detects two cards and shows CrossFireX as enabled. The Diagnostics window is blank.
I used the registry modification to disable power save on the second card. This way I can use MSI Afterburner to monitor the cards.
The problem is that it never uses the second GPU. The second GPU usage is almost always zero (maximum from the past hour or so is 6%). The first GPU is used to 99%. I have tried Crysis (SP Demo), Team Fortress 2, Unigine Heaven 2.1, 3D Mark Vantage, Mass Effect, and several other 3D applications in fullscreen and none of them use GPU 2. I also enabled the notification when CrossFire is running but never see the notification. I downloaded and installed the application profiles but that didn't seem to help.
What is wrong? I followed all the instructions for setting up CrossFire and it refuses to touch the second GPU. The second GPU is powered up (fan spinning, idling at 157/300) but the drivers never want to use it.
I don't think it's a power-related issue (anymore). I only have a 650W Antec PSU which from what I've read is barely enough to run dual 5870's on an i7 system, but when CrossFire is off I am running Folding@Home on both GPU's and on the CPU (overclocked to 4.1GHz) stable. By themselves both GPU's seem to work fine, but in CrossFire mode it isn't working properly. I have tried both one and two bridge connectors, it doesn't make a difference.