Help with troubleshooting dead comp!

[Bluff]

Hello everyone. Need some help with troubleshooting.



First, a bit of background.. Twice, when plugging in power-hungry USB devices (i.e. a DVD-RW drive) other USB devices stopped working, then when I next tried to turn the computer on nothing would happen. The second time this happened it was out of warranty, so I replaced the case (to try and fix it if it was a faulty USB port), the motherboard, and replaced the 350W with a 550W Antec.



Now to today. I left my computer on overnight converting audio files, when I wake up it’s dead. I’ve tried plugging the power supply into another comp, and it powers up the other comp fine. So I’m left with the motherboard. Is there anything else it could be? Could this problem be related to the problem I had previously? If so why and how do I stop it?



My current system specs are:

Antec 550W Truepower 2.0

Gigabyte GAK8NS Pro

AMD Athlon 64 3400+

Radeon X800 Pro

1GB RAM



Any suggestions gratefully received. J

[ross.v]

First of all
Antec truepower 550W power supply should take care of power issues.
Check if power cable on monitor and case are connected properly.
Open the case and have a look for any fan spinning inside case and LED on motherboard and case glowing (if any).
Check hard disk on different PC.
Look for the relatively big capacitors on the motherboard for any leakage or bulging surface, if so motherboard unit is going bad.
Check if there is any small speaker on motherboard if not look in motherboard manual
for speaker connector and connect case speaker to it.
Observe if there is any beeps on POST.
Check your monitor and agp card on different case.
Now check processor for it is properly seated and heat sink fan assembly securely clinged.
Test motherboard with different compatible processor if it works then you know it is processor gone dead.
Note : If you are not adequately skilled at processor job or you have not attempted it before take the case to tech. You can cause damage to processor unit.

[arch0nmyc0n]

what was the weather like last night? no electrical storms I hope...

[Bluff]

thanks ross.v, in answer to your questions - the monitor works fine, but nothing happens at all when i press the power button. No fans, lights - nothing. I only know the PSU works because I tried it in another comp. also if I place a different PSU in my comp, i get the same result, or non-result. Nothing.

The hard drive works fine.

What I would really love to get out of all of this is what you guys think might keep breaking it. This is the first computer I've ever had behave like this, suggesting it's not the power supply at my house being weird. And I use a surge protector. I even had all my plugs and computer power cables electrically tested recently.

I don;t have another compatible comp to try my Skt754 Athlon 64 in, so basically I don't know if it's that. But it survived the last two incidents I had with my computer, so...

Also, if the CPU was gone, wouldn't I still get at least fans whirring or lights coming on? Even POST maybe?

[ross.v]

Q Also, if the CPU was gone, wouldn't I still get at least fans whirring or lights coming on? Even POST maybe?
A yes

[Bluff]

so it could be both. or just mobo.


Sigh.

It seems pointless to replace parts just to have them blow up a coupla months later.

[CeeBee]

Q Also, if the CPU was gone, wouldn't I still get at least fans whirring or lights coming on? Even POST maybe?
A yes

The fans would be spinning, but with a dead CPU the computer cannot POST.
This points to a fried mobo. As a last attempt you can try to directly short the power button connector with a small screwdriver, just to rule out a bad power button. Use good light and be careful, you don't want to short some other pins by mistake.

[rsnovak]

Did you say you replaced the mobo previously in that pc? and if you did, take the mobo out of the case and just hook up the PSU & HD! reseat the RAM. To power it up, do what CeeBee said and short the power connector. Even if its is a bad p switch, that wouldn't turn off the PC! I 'm thinking of a mobo short! I have a clients pc right now that shorts out. When it does, it won't power up until you un-connect the PSU from the board and reconnect. Just a thought!