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General discussion

PC won't boot up

Nov 14, 2004 3:11AM PST

It was working fine one day but.... Anyway is there a way to tell if the cpu or motherboard is bad without another to substitute in it?

Discussion is locked

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Power supply may be more likely
Nov 14, 2004 4:11AM PST

especially over the CPU.

Why not give us the details of what happens when you hit the power button?


What fans come on, what lights go on do the drives spin? anything at all on the monitor???

Please give us something to work with.

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Re: Power supply may be more likely
Nov 14, 2004 7:08PM PST

Yeah, DETAILS!

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Re: Power supply may be more likely
Nov 15, 2004 5:10AM PST

OK. When I power up the power supply fans, the cpu fan, the case fan all turn on. The drives don't do anything at all (I've tried disconnecting them for a shorter boot time). No power on test sequence at all. No video (also tried disco this to test). No beep codes at all. So esentially nothing. I did replace the RAM and still nothing. I have also replaced the power supply with a known good one. The only things that I haven't replaced are the CPU and/or motherboard since I have no replacements. As of now I have eliminated everything elso so... The os and other stuff is pretty irrelevant. Anyone got any other ideas??

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You seem to have eliminated
Nov 15, 2004 5:43AM PST

most possibilities.

I'm a little unsure of what you mean that the drives "do nothing" when the power seems to come on.

I assume that the known good supply was an equivalent as far as what powers the CPU. 3.3 vs 12 volts.

What CPU?? If fairly old model, a replacement may be very inexpensive. AND if the CPU DID fail, you should check your cooling situation when you install a new one. CPU's can have random failures, but not very often. But it IS easier to try a CPU than change the mobo. Need a new mobo then I see an upgrade coming all around. Human nature.

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Re: You seem to have eliminated
Nov 23, 2004 9:45AM PST

I have the same symptoms I believe. Worked fine one, then next day only fans spin up. I have, however, swapped out the CPU and RAM. Only things connected to the mobo are P4 3.4 CPU with heatsink/fan, RAM module and video card. Tried PCI and two different AGP cards. I also tried two different power supplies. All parts I have swapped were confirmed working fine. Any one see anything like this before?

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Re: You seem to have eliminated
Nov 24, 2004 9:31AM PST

I have the same symptoms. Athlon XP 2000 in an Emachine. PS fan comes on, CPU fan comes on. Hard drive light is on. Power LED is off. Push power switch and the Power LED comes on, hard drive light goes out but NOTHING comes up. Installed new motherboard, system booted several times and am now having the same symptoms. Feel like it may be the CPU. Don't know. Have never seen this before.