Couple of suggestions:
1. Use another computer to find a BIOS update and run that if you can even get into the BIOS settings at all.
2. If that does not work take out your CMOS battery (should be circular and in your Mobo) and put it back in.
3. Run memtest to see if you are having problems there
4. Take out all RAM and turn the computer on, if the Mobo does not beep then its bad (make sure you have the little mobo speaker in though)
My suggestions are based on the fact that you mentioned the computer also freezes at the BIOS splash screen. This is before Windows has loaded so it points to a hardware issue or BIOS issue.
Hope this all works out for you