I was trying to fix my friends computer, it was not detecting the hard drive after format. I made the biggest blunder of my life by shorting out the fan connector (which i thought was CMOS write enable and disable). Now when i press the power button nothing turns on. As for the power supply i tested it on another machine and it is working fine. How do i know if it is the CPU or the Mobo that is messed up? The mobo i have no clue which one it is but as for the the CPU it is Pentium 3 500Mhz. What all can i check? Please help....

The kind of insult that this computer took would take out the PSU but they do have some protection. Sometimes it takes a while for the protection reset. Try the PSU in this computer again. Maybe it will work this time. If not, try to restore BIOS to default by using the APPROPRIATE jumper or by taking the MOBO battery out for a few minutes and then replacing it. If that doesn’t work, tear the computer down to the HDD, one stick of RAM, the display adapter and the CPU. Swap out different pieces of the computer (RAM, display, CPU, PSU, MOBO) to see if you can get it back. I’d swap out the PSU first if I could but usually RAM is easier to swap around. MOBO and CPU are the harder items (obviously) to swap.

were they "watching" when you did this? hope not, that had to be embarassing....

Mike thank god they weren't, it really would have been embarrasing, anyway thank you so much badboy, I really appreciate it. Apparently when i put the bios jumper to 2 and 3 "Discharge CMOS" it does not turn on. (same prob as before). As soon as i switch it to pin 1 and 2 "Normal Operation (Default)" it works fine(still does not detect HDD). Correct me if i am wrong but is the computer not suppose to go on when you have it to discharge? an in power up atleast? just as additional info my mobo is ABIT BE6 (my friend's). Everybody thanx anyway..

Oh, so the jumper was still set in the “reset BIOS” configuration and that’s why it wouldn’t boot? Great, this will be “easy” to fix. Get into CMOS and hopefully you’ll see a page that says something like “IDE HDD AUTO DETECTION”. Select it and let it do its thing. Exit CMOS saying “YES” when it asks to save the changes and you should be back in business.

Thanx badboy, that was one of the first things i tried, unfortunately that didn't work. I made the HD slave to CD rom cable and it is workin, telling me that there is sth funny in the port where IDE cable is hooked to!