Hey ppl im new to this site im hopeing you can HELP me with thei problem

My COMPUTER at my work , its doing nothing , power lights come on hdd light stays on even with hdd no in system.

It all happened after a power cut/(1800w cooktek microwave bag warming systme fliped the breaker)

Computers ARENT even on the same system as the one that went out but after i flipped the breaker back on the secondary computer (the one thats connection to a printer and thats its only job)

Well first windows froze and i had to press reset , after that i get no graphics

Hears a short discription of the computer

(self made)

350w power uinit
MSI mother BOARD
Intel celeron D 2,4ghz
for the rest built in graphics and sound (on board)

I have tryed s far

Another power supply other (known working ram) in other slot same slot
using jumper to reset bios
Have also tryed to start with out fdd keyb,etc only mobo and power and monitor

Any idea whats rong with it , and for hte rest if i turn on wiht all connected cd rom flashes
floppy flashes
hdd light just stays on , and also i dont get any beeps atall (dont know if speaker is working/connected good)
Funnily enough, same with my computer, after i (probably) killed it with an unsuccessful processor TRANSPLANT, and i have no idea :-?. i am sorry . but it is not your speaker connection because it is a pc speaker and not detachable.