So here's the deal. . .

I have an old desktop computer running Slackware, AMD Athlon 800MHz, Abit KT7 motherboard, etc. Last fall, during a thunderstorm, the power went out for a few seconds. When it came back on the computer wouldn't boot. The fans spin, the hard drive and power LEDs light up; but I don't get a POST beep, nor does the monitor come out of standby.

I took the computer in to a local computer shop and the guy there told me that it was most likely my motherboard that had died. He tested out my power supply with one of them power supply testers and said that the power supply was fine.

Fast forward to March. I decide to bid on a used Gigabyte GA-7ZXE v2.1 motherboard on FleaBay. I won the auction and the motherboard arrived and I installed it, but I still get no POST beep when I turn the computer on nor does my monitor come out of standby.

I've tried removing all the PCI cards and leaving just the RAM, CPU, and video card in, but still nothing. I've tried to boot it without the CPU, nothing. I've tried to boot it without RAM and with just one stick of RAM, nothing. I've tried unplugging all the IDE cables, still nothing. I've tried removing the CMOS battery for 5 minutes, and then reinserting it, still nothing. No POST beep, nothing displayed on my monitor. But the fans spin, and the power and HD LEDs still light up.

Today I took the power supply to another computer shop and had them test it again, they said it was fine.

So now I'm beginning to think it might be the CPU. But shouldn't I still get at least some kind of POST beep, even if the CPU is fried (for example, multiple beeps telling me that the CPU is bad)? Or, in order for POST to work, does it require a functional CPU?

Hi,
Sorry to read of your troubles..I would think you MUST have a working CPU in order to POST..
My first thoughts would be to unplug all devices except Keyboard monitor and mouse if not already so..Since you un-plugged the battery you should first set the BIOS to safe mode if you can find it..(may also be the default settings)
Then go into your BIOS and see if the supply voltages are correct..Don't assume the testers are accurate..Look at the 5 volts,12volts,3.3volts, and especially the core voltage that your CPU requires..You can go to the Mfgr. website to get the correct voltage..If that fails you can remove the Heat sink grease and read it on the CPU but DO re-install the HS compound grease..
CPU,motherboard failures,and many other things can cause the Bios not to post..
Meanwhile others may offer more suggestions,
goodluck,
jolphil
Edit: also check that you have the correct CPU settings
for multiplier and front side bus...