I havea homebuilt computer, about 2 months old. It has been working perfectly until today.

Build is as follows:

XFX nForce 790i Ultra SLI
Intel Core 2 Quad Q9450 LGA775 'Yorkfield' 2.66GHz
OCZ 2GB DDR3 PC3-16000C9 2000MHz
EVGA GeForce GTX 280 1024MB

So I decide to play the L4D demo and Steam kindly informs me that my video card drivers are out of date. 3 Clicks later drivers are updated from the nvidia site, asks me to reboot, and now it's hanging.

I'm not particularly savvy with bios, but any ideas would be appreciated. I can't imagine this is a hardware conflict as everything has been fine up until now. I'm assuming it has something to do with the new video card drivers......anyway I can fix this easily? I would really like to rollback the driver but seeing as I can't get into Windows I can't see how to do this? Any other ideas?

Thanks in advance,

Try entering the BIOS setup. Select and enter the PNP/PCI configuration setup (if available).
Enable the "Reset Cofiguation Data". Save the BIOS setup and restart.

Usually, if a system hang at this stage its down to the BIOS settings. You may need to reset the BIOS / CMOS settings to the factory or default settings as you are not "savvy" with BIOS.

NOTE: This couold also be down to harware.