dead cpu or dead mobo?

[stackner]

i have two main computers setup and i had a second old slower one setup for storage so it was powered on a lot. the cpu is a celeron 1.3g. what has happened is one time i turned it off and then later went to turn it on and i get nothing at all. the pc case power supply fan turns on but nothing else starts up. i cant even get to bios. if i remember right i think the power light turns on on the front of the pc also but i am not sure now as ive taken the pc apart. i suspect the cpu becouse i have an old celeron 500g cpu that i can not use with the mobo but i pluged it in and still did not get bios or anything but the pc seemed to fire up the hdd's. i will post more info after work tonight when i put it back together and fire it up again. thanks.

[redwudz]

Do you get any BIOS beeps? That may tell you the problem.

But dead computers are hard to diagnose. You have to do it mainly by substitution. If the power light and the drive lights come on, then it may not be the power supply. But if you have a spare, try a different PS.

Unplug all drives except the boot drive. Remove all cards except the video card. Check all connections, reseat the video card and the memory modules.

Try substituting the memory modules with known good ones. Same with the video card.

What's left over is the MB or the CPU. Since you got a little further with a incompatible CPU, then you may be correct about the CPU failing. There is no easy way to test that either, unless you have another MB that will work with the CPU you have.

In that case, either replace the CPU or upgrade the whole system with a new MB and CPU.

[Jeremiah58]

Exacly the same thing happened to me today and it was the video card.
Check the topic if you want to see the details:
https://forum.videohelp.com/viewtopic.php?t=301355&highlight=

[MOVIEGEEK]

It could be the PSU(power supply unit),just because the fans work doesn't mean the power transistors aren't fried.Use a VOM meter to check the voltage.

[stackner]

thanks for all the replys. i just pluged it all up today and with the orig cpu in it when you press power NOTHIONG turns on not even the lights or power supply fan. when i put the 500g cpu in thats not compat with the mobo the fans come on and the hdd powers up but no bios sounds. makes me belive its the cpu....

[ROF]

i wouldn't continue plugging in an incompatible CPU. You are liable to screw something else up.

[Bjs]

Check the reset switch is not damaged .

The pc pass's current through the reset switch to test power on state before firing up the system , if voltage is not detected , nothing work's ... on some newer system's , all drive's and fan's will power up .

Make sure the reset switch is not stuck ... which appear's as an closed circuit to the pc ... this prevent's the boot process from continuing.

[Doramius]

Maybe, I'm overkill, but I usually just forget the whole testing and build a new PC. I'll go on eBay and sell the old stuff as 'untested non-functioning equipment'. I don't always have the time to test things and unless it's REALLY expensive, I don't even try to bother with it. You said the PC was old, and a new mobo, CPU, & RAM for something even 'bargain bin new' would be better than what you have. I don't think you'd be disappointed at all.

[lenti_75]

the mobo should start wihout anything else on it.

looks to me like the mobo is the problem.

[DarrellS]

Take the motherboard and power supply somewhere and have them tested.
My brother had this problem a couple of months ago on a brand new machine and after taking the MB and PSU to Fry's and finding that they were ok, he bought a new case and it solved the problem.
That was what the ASUS website recommended. Testing everything out of the case.

[ROF]

Maybe, I'm overkill, but I usually just forget the whole testing and build a new PC. I'll go on eBay and sell the old stuff as 'untested non-functioning equipment'. I don't always have the time to test things and unless it's REALLY expensive, I don't even try to bother with it. You said the PC was old, and a new mobo, CPU, & RAM for something even 'bargain bin new' would be better than what you have. I don't think you'd be disappointed at all.

Next time you do this can you please PM me. I am always looking to steal good equipment from people to lazy to troubleshoot a solution. I recently took two 2.0Ghz processors from people who sold me their barebones systems for next to nothing because it did not work. One had a bad power supply. The other one I never did figure out why it was considered dead. I powered it up and all has been fine.