My wife has a computer with an ASUS P5ND motherboard that's been failing to boot lately; I'm not sure what's causing it, but it may be a motherboard problem, so I'm posting here. Essentially, what happens is that the BIOS boots partially (including a successful sounding startup beep) and then the screen goes black. This had been occuring during the Windows boot process (I run Vista; the Windows logo would appear briefly, and then the screen would go blank and the booting process would hang), but now I'm getting a message saying that the BIOS post failed and then the screen goes black. I can then press delete to enter setup, but the screen blacks several seconds afterwards.

Admittedly, this may be a video card problem (feel free to move it if so), but my wife noticed no graphical artifacting or other signs of damage (other than a Skyrim crash to desktop, which is probably par for the course for the game). For what it's worth, she has a GeForce SLI setup of some kind (I'm not sure what, but if it would be helpful, I can check); I've tried reseating the cards and the bridge to no avail (though immediately after doing this, I *was* able to view the set-up screen successfully, without the screen going blank; further reboots led to the blanking set-up screen again).

Anyway, if anyone has any suggestions as to the nature of this problem before I take it in for repairs, I'd greatly appreciate them. I'm pretty mystified, and I've not seen anyone discussing similar problems on the Internet.

It may very well be the motherboard or even the power supply... SLI setups require a lot of power