Faulty PSU, motherboard or CPU?

GSD

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Dec 8, 2008
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Hi all,

My parents computer started randomly freezing up a couple of days ago and it gradually got worse to the point where now it won't even show anything on the screen.
All of the fans and the hard-drive, etc. boot up OK, the motherboard light is on, but none of the keyboard/mouse lights work and nothing is displaying on the screen. I also don't hear any beeps when it starts up.

So far I have tried a different GFX card, RAM and hard-drive but it still won't display anything.

I have tested the PSU using a multimeter and the 5v and 12v rails are reading OK; I'm not sure how to check the 3v rails.
The PSU is a Corsair and it's only 6 months old so I doubt it's that. If the 5v and 12v rails are reading OK, does that mean it's probably not the PSU?
I'm suspecting it's either the CPU or motherboard now but I don't have any spare to test it with.

What do you think it is and what should I do next?

To be honest this PC has been a pain in the backside. It blew up just 6 months ago and I needed to replace the PSU, motherboard and RAM.
Here are the specs:
Intel P4 Northwood 2.6Ghz CPU (Socket 478)
ASUS P4P800SE Motherboard
512MB Kingston RAM
nVidia FX5200 GFX card
Corsair CX 400W PSU
Maxtor 120GB hard-drive.

As you can see it's quite an old machine now, except for the PSU which is newish. I'm tempted to just upgrade the CPU, motherboard and RAM.
 

tribulator135

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Apr 21, 2010
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It seems to me like it is your mobo. take your cpu out and start it, most mobos will say something along the lines of "no processor" if they are working. this should help you pinpoint whether it is your proc or mobo
 

GSD

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Dec 8, 2008
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That's what I thought.

I've decided to upgrade the CPU, motherboard and RAM instead of spending more money on replacing these dated components.

This is the second time in 6 months that an ASUS P4P800SE has died in this PC.

 


:pfff:

Your source for this?

Without the CPU, the motherboard will just sit there quietly and the monitor will tell you that it is seing no video.

Admittedly, that would be a marvelous feature to have.