Dead mobo?

Six6siX · 19 May 2006 at 15:27

Hi, my friend just rang me having a few problems with his PC and I've been guiding him through some basic troubleshooting over the phone, but I'm at a dead end now.

All I know about the PC is that it has an Asus P4S800-MX Motherboard, Some form of P4 CPU, 1GB RAM and an All In Wonder 9800 Pro. It was a pre build from OCuK in fact.

Anyway, it was working fine at 12 this afternoon, was turned off, and now, 2 hours later refuses to boot. Just turns on, no monitor output, fans spin, no beeps.

Here's whats been done so far:
- Removed Graphics card (no beeps, fans spin)
- Removed Memory (no beeps, fans spin)
- He's removing CPU at the moment.

Would I be right in thinking that if it beeps with no CPU, its the CPU that has died, and if it doesnt beep then its the Mobo?

Any other suggestions?

split · 19 May 2006 at 16:15

I just repaired a PC that wouldn't turn on. (totally dead)

Did this and got zero volts.
New PSU, and away it went.

If the CPU has gone, you usually get something happen (but not always)

BTW, if you dont have a DMM, then the fan on the PSU should run as an indication it is working.
DMMs better tho if you have one.

Six6siX · 19 May 2006 at 16:22

Link is timing out for me :confused:

Never considered the power supply because fans were spinning etc - I'll ask him to check the PSU fan though.

An update: He has tried booting out of the case, with no CPU and there is no beep, but fans spin.

I'm thinking dead mobo...?

split · 19 May 2006 at 16:26

Never considered the power supply because fans were spinning etc

But you didnt say that above. (yes you did, my bad

Link works for me, try..

http://www.ochardware.com/articles/psuvolt/psuvolt.html

On most motherboards, you get a no CPU beep, but it's not an exact science.

I suppose you have totally cleared the CMOS (removed battery etc)

O'h and make sure the case speaker is connected else you won't hear any beeps

If you look here and here you can see that most BIOSs beep if you have a CPU error.
Ive seen people remove the CPU to get a bleep to indicate either board or CPU error, but it's not that exact.

Duh, also in the sticky at the top of this forum as well

iraiguana · 19 May 2006 at 17:48

the fact that u say u dont get any beeps makes looking for beeps when u take stuff out an interesting one. have u tried replacing parts as that is only only true test, could be that the graphics card went but mobo not detecting an error as it doesnt think it is there and doesnt feel the lack of one to be a problem ? just need some stuff to compare with.

Six6siX · 19 May 2006 at 20:48

Hi thanks for the replies

iraiguana said:
the fact that u say u dont get any beeps makes looking for beeps when u take stuff out an interesting one. have u tried replacing parts as that is only only true test, could be that the graphics card went but mobo not detecting an error as it doesnt think it is there and doesnt feel the lack of one to be a problem ? just need some stuff to compare with.

He's still had no luck with it so I've told him to find a friend with some similar components to try with his machine. Hopefully that will give some useful info and is probably, as you say a more proven method - just a bit impossible if no one he knows is running AGP with a socket 478.

split said:
Link works for me, try..

http://www.ochardware.com/articles/psuvolt/psuvolt.html

On most motherboards, you get a no CPU beep, but it's not an exact science.

I suppose you have totally cleared the CMOS (removed battery etc)

O'h and make sure the case speaker is connected else you won't hear any beeps

If you look here and here you can see that most BIOSs beep if you have a CPU error.
Ive seen people remove the CPU to get a bleep to indicate either board or CPU error, but it's not that exact.

Duh, also in the sticky at the top of this forum as well

I told him to try clearing the CMOS, and that made no difference - I also had a look round to find some info on any specific troubleshooting guides with this mobo but no luck yet.

Now that you mention the speaker - I remember him saying saying it was definately connected, twice lol. I still cant seem to get anything out of that link though. Even the main site doesn't load for me!

I'll have to wait and see what comes up, cheers for the advice guys