Dead Computer? - Help needed

Daemonic

The story so far....
Booted computer the other day and after a couple of minutes it froze, not something i can recall it doing recently. I hit the reset button and it never came back. Power comes on, fans spin up, i hear the optical and hard drives spin up but nothing else. No boot screen, no bios beeps, nothing.
So, i removed all but the necessary components, cpu, memory and used on-board graphics. First boot nothing happened. Removed one memory stick, nothing, swapped in the other one and i got a boot screen so CPU and one dimm appeared ok. Next time i tried booting it with the exact same components i'm back to nothing happening. Reseated memory and CPU and still nothing.
It looks like i have an ok CPU and one good dimm, although i'm thinking given the single boot up the other is probably ok too.
Spec of the barebones system is a Pentium 4 3.6Ghz CPU (not overclocked), 2 GB of DDR memory and Abit IG-80 mobo.

Anyone got any suggestions as to a next step in trying to get it back working again? Any help is appreciated.

sdanseo

Change HDD would be my first guess if you have another one lying around - otherwise try a PCI GFX card if you have one, or [longshot] is your monitor working properly?[/longshot]

DonkeyStyle \o/

It looks like i have an ok CPU and one good dimm, although i'm thinking given the single boot up the other is probably ok too.

Or to pose another hypothesis - both sticks of ram are actually fudged... one slightly less banjaxed than the other and you got one last dying gasp from the slightly better one before it finally gave in.

All I can suggest beyond swapping out components with spares until you isolate the culprit is using the CMOS/BIOS reset jumper to restore the system defaults.
It at least rules one more thing out.
I'd say if you could confirm the ram as working/dead in another machine (memtest86 or at least a stable OS boot), you'd be another step closer.

It's this kind of situation that makes having multiple PCs a God-send.

Daemonic

The story continues....
Tried booting again with boot HD plugged in and hey presto, Windows loads....then i plug in my usb mouse and the PC died, powered down completely. Now I'm thinking something on the mobo is damaged, maybe capacitors because if i leave it long enough i get a successful boot.

christophicus

leave it long enough once its turned on , or betwwen boot attempts? souds ike mobo or psu is gone.

DonkeyStyle \o/

Will it not POST if the HD is disconnected? :eek:

Daemonic

christophicus wrote:

leave it long enough once its turned on , or betwwen boot attempts? souds ike mobo or psu is gone.

PSU could be it...only boots occasionally with most components removed...hmmm.

Daemonic

DonkeyStyle \o/ wrote:

Will it not POST if the HD is disconnected? :eek:

Only sometimes, successful boots seem to be just random. I've stripped it all the way back to mobo, cpu, ram and even that fails most of the time.
So, what would be the recommendation, new Case/PSU (current one is non-standard so can't just replace the PSU) or a new mobo??

Daemonic

Getting stranger and stranger. Tried booting again expecting the pc to die quickly, but no, it stayed up for about 45 minutes so i decided to reboot and put the suspect dimm back in. Hung on post so removed dimm again. Booted and set bios setting again, having reset it earlier. Saved setting, pc doesn't boot. Powered off and on again and it's been up about 15 minutes with one HD and one DVD drive plugged in.
The mobo drivers cd had a utility to monitor voltage, temps etc and all look ok. Anyone know of a utility to test the rest of the system? Can't use Memtest86 cause i have no floppy drive or working cd writer without the PC getting fixed

Daemonic

I think i have this narrowed down to bad dimms. PC never boots with one of them installed. With the other it boots intermittently and will then hang, sometimes after a minute or 2, sometimes after maybe 30 minutes. However I still have a slight worry about the PSU.
So, would a dodgy PSU cause the PC to boot intermittently and then hang?
I know bad memory would prevent a boot up and would cause the hangs, but would it cause the PC to power up and then shutdown within a few seconds?
Any thoughts and opinions on this are appreciated.