(E-Mail Removed) wrote
> My PC is not working anymore and I need help in figuring
> out what part is damaged so that I can buy a new part.
> The VERY very strange thing is that it happened graudually, you might call
> it slow death of a PC. I compare it to a person dying slowly from cancer.
You can get that effect with bad caps on the motherboard.
> Everything started 2 weeks ago, I was working on my PC when
> it suddenly froze/shut-off. By froze/shutt-off, I mean the monitor
> shut off and the system stopped working, but the power leds
> harddisks,CDs, were still on power.
Likely the cpu stopped.
> After I pull the plug out and put in again, the PC works again.
> For the moment I was just glad it worked. As days passed
> these strange shut-offs happened more often, until 3 days
> ago, this time pulling the plug off and on again didnt help at
> all. I left the PC alone for 4 days and tried today again. VERY
> strangely it worked, but only for 1 hour and stopped then totally.
> I started the problem-diagnostic by removing all non-essential
> parts of the PC. All was left in the PC was:
> 1) Power supply
> 2) Motherboard( with on-board graphic card)
> with a Pentium 4 CPU, and
> 3) 2 x DDR RAM
> Now, this is what happens when I press the ON switch: power
> supply fan starts turning, the power and harddisk led are turned
> on, but the screen is black. I also noticed that the power switch
> is not working, hence I can not turn the PC off by pressing the
> ON/OFF switch again, I rather have to pull the plug off.
Thats all evidence that the cpu isnt running anymore, particularly
the power switch effect since its a contact closure that the cpu
decides what to do about based on how long is held in etc.
> I am sure of:
> 1) Its not the monitor, because It worked somewhere else.
> 2) Its not the DDR, because I tried using each
> one seperatly and still nothing happened.
> 3) Its not the power supply, because I tried a
> different power supply and still nothing happened.
> I came to the conculsion that it must be either the CPU or the motherboard.
Yes, but cpus dont fail very often and not normally like that.
> I would like to know which one you think is the damaged part,
> the CPU or the motherboard so that I can replace it?
Almost certainly the motherboard. Check for bad caps. Those are
the usually blue or black plastic covered post like things that stick
up vertically from the motherboard. The tops should be flat. If any
are bulging or leaking, you've got the classic bad caps failure.
> And I would like to know if the symptoms I described
> are truly that of a damaged motherboard or CPU?
Motherboard.
> I am thankfull for ANY advice on this matter.
Try running the motherboard loose on the desktop, you
can get an intermittent short to case and running it lose
on the desktop is the best test for that. Unlikely thats
the problem tho, its much more likely to be bad caps.