A few days ago I received my second 4850 in the mail. My problem is that one of my cards simply is not being used at all. I used MSI Afterburner to view my performance while playing some games. My result was 99% usage on the first card, and 0% usage on the second card. I did this playing Black Ops and also CS:S to make sure it wasn't Black Ops having poor optimization. In CCC and GPU-z it claims Crossfire is enabled, yet in ATI Tray Tools it says its unavailable. My system is as follows: Phenom II X4 925 @2.8 ghz (non-overclocked) MSI 790x-g45 Motherboard 4 GB 1600 ddr3 RAM Gigabyte 4850 1gb XFX 4850 1gb Windows 7 32 bit From what I have read online this configuration should work fine in crossfire. Also, I am using 1 Crossfire bridge which is a MSI crossfire bridge that came with my motherboard. If anyone sees what could be wrong I would really appreciate the help.