Black Screen, Computer Won't Post, No BIOS, Help!

[doodah12]

Computer was having heavy hiccups where it would start to reboot when running semi-intensive programs. I was going to reformat HD in a few days, and start over. But now the computer screen suddenly went black, if I reboot, nothing comes on the screen, and I can't get into BIOS. I hear nothing, no beeps, no post. The HD light comes on, stays solid, and goes off. and the floppy drive doesn't light up . Everything seems to be powering up. All fans are running. I reset the CMOS jumper, changed the CMOS battery, but still no post.
My CD and DVD drives light up, so I put in my XP install disk hoping to do a repair or install from that, but still no boot, just black screen and no beeps.
Computer was running well up until the hiccups, anti-virus was up to date, spyware, adware was under control.
Any help would be greatly appreciated.
Thanks,
Scott

[zman88]

My bet would be the MB is all done. I had the same prob with a 533-C . But you can check the power supply by replacing it if you have one laying around, switch out the memory,cpu, and vid card (one at a time). The 800 is a good board but old. I wouldn't spend too much money troubleshooting it.

[doodah12]

I do have an extra power supply laying around, but please tell me how I should go about replacing things 'one at a time", not quite sure which order to do things in.
Thanks

[INVALiD]

I experienced a similar problem recently;
No boot, no POST, no error beeps, but the case, psu, and CPU fan would spin.
Initially no HD light indicator activity or CDROM/floppy light and no rear case fan movement. The computer seemed to huff and puff for short intervals at at time before I could get the rear case fan, CDROM, and HD indicator lights to come on by continuously toggling the start and reset buttons.

It took 4 hrs a fiddling around (making sure everything was mounted properly) and airing out the MB with a can of air spray before it would finally boot.

I have no Idea what it was. I'm thinking it was a short of some kind.
I just hope it doesn't happen again. It's a big time pain in the ****.
Thought my processor was dead for awhile there...ouch.

I tried moving the CMOS pin to recovery mode and removing the bat for 10 min...no go.

Tried removing many power connections from diff devices and reseating them to no avail.

This has happened twice so far. When I finally did get to boot everything seemed fine memory, clock speeds, voltages all were within norms.

I rolled the bios back to it's factory default (1 ver. earlier) and got really weird
rear case fan activity: it would continuously cycle between high and low. Reflashed bios to updated current ver. everything seems well now.

I havn't messed around too much in the bios previously and have never experienced any instability issues when running load, despite my concerns over the SFF heat issues with the FN FragboxPro.

[zman88]

By saying one at a time , I mean try one thing at a time . Like the power supply for example. If that doesn't help put the original back in. Then memory,vid card etc... I can tell you when there is no beeps it's not a good thing.