Bad Bios checksum. Starting BIOS Recovery

Hello,

This is what happened:
I was just surfing the internet and using MS Paint then suddenly, my computer restarted...
when it came back on, it showed the message:
"We apologize for the inconvenience, but Windows did not start successfully...etc..."
it gave me options to continue in safe mode, start normally or use the last good configuration.
I tried allof them but every single one of them resulted in a blue screen that flashes really quickly with white words written in it.

I've tried not selecting anything and letting it "start windows" in its own "in 30 seconds". And still it goes to the blue screen.

I could only read the first phrase of the blue screen... it was something like: "A problem has occurred and Windows has been shut down to protect damage to your system." or something like that...

And then it says that it could be because of hardware/software that's been unproperly downloaded or something and to make sure that it's downloaded correctly.

I tried pressing F8 when windows was booting and I tried booting from the CD... I think it only made it worse
now, when I turn it on, it says:
"GeForce FX 5500 BIOS Version 4.34.20.87.ON Copyright (C) 1996-2003 NVIDIA Corp. 256.0MB RAM

Bad Bios checksum. Starting BIOS Recovery"
then it started looking for a CD or a Floppy

I tried restarting it again and now, it won't even start.
The monitor just displays:
"Self Test
Check your PC and Signal Cable
Monitor is Working"

Someone please help!