MSI 890GXM-G65 + HD5970 = BIOS Failure?

Submit2Genocide

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Oct 10, 2011
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I'm having quite a bit of difficulty with my most recent upgrade, and I'm hoping someone here may be able to help; I'm a first-time poster, long-time lurker, have searched quite a bit for a fix, and also followed each of the steps outlined on "PERFORM THESE STEPS before posting about boot/no video problems!". I work for an IT firm, and so I did ask a number of my colleagues as to their opinions, but the best I received is that perhaps the graphics card is DOA, and I don't agree with that one. Here's my current setup:

CPU: AMD Phenom II 1100T X6 (3.3GHz)
GPU 1: AMD Radeon HD5970
GPU 2: AMD Radeon HD5970
Motherboard: MSI 890GXM-G65
PSU: OCZ-ZX1250W (1250W 80 Plus Gold)

I had previously had an Nvidia GTX 470 and a 560, which worked fine, before deciding to swap them out for the dual AMD HD5970. I believe I've isolated the issue and think it has something to do with the BIOS settings - after disconnecting each of the components, plugging them in one by one, and powering on the unit I verified that I'm able to POST with the CPU and memory intact. If I try adding one of the AMD Radeon HD5970 cards the fans begin to spin, but there's no beep nor display. If I reset the CMOS (by unplugging the PSU and removing the battery), place the battery back in, and then power up with the card still in the computer boots to the BIOS (with the display obviously working). Once I set the settings and restart I run into the issue once more where I'm unable to power on the computer until I reset the CMOS once more.

I've confirmed that the display settings in the BIOS point to the PCIe card, and have tried both "Load Fail Safe Settings" and "Load Optimized Settings", but neither seem to fix this. What am I missing? If you need any more information or pictures please let me know - this is day 3 without a solution and I'm unsure of what to do now.