Here's what I have: Mac Pro w/ Leopard 10.5.1, 2 x 2.66GHz Xeon, 5GB RAM, ATI x1900 graphics card, 4 x 320 GB HDD + 1 x 250GB startup disk.
I've encountered several problems trying to get Windows installed. The first one was coming to the realization that you can't create the Boot Camp partition on a RAID disk. That's when I discovered there were two extra SATA ports on the mobo. I plugged in my extra 250GB drive and successfully created an 80GB partition with Boot Camp Assistant (and also made it my primary startup disk for OSX). The next thing I discovered was that those two extra SATA ports are not recognized by Windows, so I had to rearrange my hard drives and put the boot disk with the Windows partition into the #1 slot. After I got that figured out, I was able to boot with the Windows XP CD, format the partition as NTFS, and successfully install Windows.
But this is where I get stuck.
Now that Windows is installed and I've successfully installed the updated Boot Camp drivers, both my monitors go black after Windows loads. I see the XP startup screen, but after that I get nothing. I can hear the startup sound through the internal speaker but I'm forced to hit the power button because I have no display. There's another problem too - and it might be related to the black screen. Every time Windows starts to load (and also in Windows before I installed the updated drivers) the displays would get all messed up and there would be these weird vertical scewed lines and random DOS characters all over the screen. It would sometimes go away if I restarted the computer, but that would only work every 5 restarts or so.
Initial blank screen when Windows starts to load...

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Windows install screen...

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Windows boot screen...

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Anybody ever heard of these problems before? I'm guessing that it has to do with either the video card or the monitors, but I'm sort of at a loss for what to do next.