WTH just happened ?

I turned on my computer and it popped a message "BIOS Checksum Error. Starting recovery ...".
It started searching my floppy drive( non-existent :P ) and the Cd-Drive for the BIOS ROM.
Fortunately, I had the support CD at hand and quickly pushed it into the CD-Drive.

Up came the message :

"M2N-MX.ROM detected
Starting Erasing...|
Starting programming ....| "

Then the mobo beeped twice-thrice and the computer restarted. And, the BIOS checksum error message popped again !! WTH !! i just saw it getting flashed !!

Happened 2 times in a row....frustrated, i decided to take out the mobo manual (dunno why i didn't take it out earlier ... :P)

It had 2 full pages regarding BIOS recovery... one way was to press Alt+ F2 before POST to start ASUS' "EZ Flash Utility " that would apparently help me flash my BIOS.

Computer restarted. I pressed Alt+F2.
The utility started and searched my Cd-Drive for a BIOS file.
Up came the message "M2N-MX.ROM detected"
and immedialtely followed by "Error ! the ROM file is outdated and cannot work with the hardware "
WTF !! This is the BIOS that came in the manufacturer's CD !!

I was starting to freak out... Fired up my old machine and downloaded the LATEST BIOS for my mobo, bought a CD and burned it onto the disk.

Computer restarted.
Up came the message:
"M2N-MX.ROM not detected !"

huh?...Sigh, the file i had downloaded had a different name ....fine, i'll just have to rename it and burn it again....I removed the Cd from the drive and instead of pushing the "power-off" button, accidentally, pushed the "restart button"...

My BIOS was detected !!

"There is a CMOS checksum error :
Press F1 to start recovery
Press F2 to reset to default settings and continue " ?_?

F2 pressed.
The screen went blank and up came the familiar message
"GRUB Loading stage 1.5. "

Wheeeee !! problem solved !!
But WTH just happened ??? The computer was running fine until yesterday ...
My guess is a faulty SMPS which isn't providing the required current at the required voltage to the mobo....
Any pointers ?