This has got me tearing my hair out....

[wheezergeezer]

ZZaxx99,

a few years, I decided if my infinite wisdom
to build my own PC............Rings a bell ehhhhhhh, well I put it all together beautifully, switched on .................Zero, checked all components were connected , rechecked , switched on again.............zero
this went on for some time,took it all apart , reconnected, everyone at home kept out of my way, I was evil, bad tempered miserable ,cursing myself for being so stupid , I was pretty close to jumping up and down on the Mother........er , with an axe no less, I took a break went back and realised that the fan at the back of the pc, wasn't working, Meanwhile the supplier had decided become a mail -order business, which ment I couldn't go back to the store to exchange, I had to post it back !I which I did, waited an age for a replacement, eventually got one, fitted it and switched on the pc..........Zero.............oh ****e.................phoned the support helpline which didn't comprehend the word help or customer service, even though they had sold me two faulty PSU's, now I'm close to a heart attack, angry, P/off , and 200% frustrated
decide to cut my loss'es and buy one from a shop, put it in and fired her up first time.................
Would I do it again...................NO,NO NO, my friend there come's a time when you have to get someone who know's more that you do to fix it, pay him and get on with your life, its cheaper in the long run................good luck

 

[wheezergeezer]

zzaxx99,
just a thought , are the motherboard and CPU compatable ? i.e. is the AMD CPU recommended for that Type of Motherboard,
is the PSU working ,i.e. can you see or hear the fan working at the back of the unit ?

 

[Bunyip]

I have built a few computers. I had a similar, intermittent problem with the machine starting when I pressed the on button only to immediately power down (ie: the CPU fan would start, the HD would start, but it would then power down within a couple of seconds). The only way to get it to attempt to restart again was to remove the power cord and plug it back in. I was able to get the machine started after some messing about. After some months, the PSU gave up and by replacing it the problem went away. Originally the problem looked like a motherboard, memory, CPU, HD type problem.

Another place that I have found useful for information is:

http://www.amdmb.com - either search the forums or post your problem there.

Hope this helps.

 

[Bill G]

This post is compulsive reading for me If and when you find the answer you must tell !!
Good luck

 

[zzaxx99]

zzaxx99,
just a thought , are the motherboard and CPU compatable ? i.e. is the AMD CPU recommended for that Type of Motherboard,

Yes - the board will accept anything up to a XP3200+

is the PSU working ,i.e. can you see or hear the fan working at the back of the unit ?

Yep - fan spins up, very briefly, as do all the other fans. Then they spind down to a stop again

 

[ChartMan]

Just thinking about this again..... Are you sure there isn't a short circuit on the motherboard somewhere? When there is a short on the motherboard ( or something plugged into it- memory/card/modem etc) then the PSU will power up, and within a second or so, will detect an over current situation, and then shut down.
So to eliminate that possibility, remove every thing, and I mean every thing. All fans, memory, add ins , CPU etc, leaving just the MB and PSU.Remove all ancillary plugs from the case- power on LED, HDD led, reset switch, leaving just the power on switch. When you push the power button, the PSU should start up ( 12v fan on the PSU will spin so you know it's on) and stay running.....
If that works, you can start putting things back together one by one, starting with all the case connections, then the fans, including the CPU fan but NO cpu. Don't forget the MB speaker.Then onto the CPU with fan. With no memory, or Video card, the POST will fail mem test and beep..... If you have on board video you won't get a video fail POST beep, obviously.
Maybe you did all that already....

 

[Hughmac]

Yet another thought, is the reset a "make" or "break" action. ie does the reset switch have to be "made" before the cpu will run and "open" to reset.

Just thinking that all those components cant be duff! Could it be a motherboard link or switch settings.

 

[ChartMan]

Reset is normally open, close to reset.

 

[zzaxx99]

Just thinking about this again..... Are you sure there isn't a short circuit on the motherboard somewhere? When there is a short on the motherboard ( or something plugged into it- memory/card/modem etc) then the PSU will power up, and within a second or so, will detect an over current situation, and then shut down.
So to eliminate that possibility, remove every thing, and I mean every thing. All fans, memory, add ins , CPU etc, leaving just the MB and PSU.Remove all ancillary plugs from the case- power on LED, HDD led, reset switch, leaving just the power on switch. When you push the power button, the PSU should start up ( 12v fan on the PSU will spin so you know it's on) and stay running.....
If that works, you can start putting things back together one by one, starting with all the case connections, then the fans, including the CPU fan but NO cpu. Don't forget the MB speaker.Then onto the CPU with fan. With no memory, or Video card, the POST will fail mem test and beep..... If you have on board video you won't get a video fail POST beep, obviously.
Maybe you did all that already....

Some good ideas there - I'll give them a go, thanks - well, apart from the speaker one. I was looking at this again yesterday, and I discovered that the reason that I hadn't connected the speaker previously was that the case doesn't have one, which is a first for me - never seen a case that didn't come with a speaker before.

 

[zzaxx99]

(A door creaks opens. A figure struggles through, brushing cobwebs from his hair. He emerges blinking into the light...)

Yes, it's round 343,454,462 of the "why doesn't my damn PC work" thread.

A new concept in this message though - some actual progress (of a sort).

I tried the Chartman idea of methodically adding things until the PSU stopped, and managed to get to the point where the CPU fan would actually stay on! (This may not sound like much, but it's earth-shattering progress compared to what's gone before).

I then plugged in the diagnostic bracket, and it said that the CPU was damaged or not inserted correctly. Hmm, OK, let's check. Sure enough, the processor wasn't correctly seated. Got it set correctly, latched it in, powered on again...

... and the machine shut down after 1-2 seconds. Can't be the processor, surely? Let's try the other processor... same thing.

Next experiment - power on with ZIF socket unlatched - fans stay on. Close the ZIF socket and retry - cuts out after a couple of seconds.

So, what have I learnt:

• Well, looks like it isn't the RAM after all
• Looks like it isn't grounding
• Looks like maybe both processors are damaged???
• That would make 3 damaged processors in a row, which is a hell of a losing streak... I've never had a processor failure before

Ideas anyone - is there anything else that could be jinxing this, or have I really got 2 duff processors?

 

[adrianallen99]

I have multiple processor failure, what it actually turned out to be was the motherboard was faulty and frying the processors. You try processor in Motherboard A and it fails, so you try processor in Motherboard B and it fails. So I assume it is processor that is faulty. So I try Processor 2 in Motherboard A and it fails, try processor 2 in motherboard B and it fails. So I start to wonder, do I have 2 faulty boards, or 2 faulty processors?

I then try a board I know works and it fails, so I assume its not the board.

I then try processor 3 in Board B and It works, so I breath a sign of relief. Stupidily I try processor 3 in board A (just out of curiosity) and it fails, so I then assume problem is board A. I then put processor 3 in board B and it fails??

It turned out that as soon as I tried the processor in the damaged board it also damaged the processor.

Anyway, probably wrong, but just a thought.

 

[wheezergeezer]

ZZaxx99,

Dude, you've got a serious problem, its seems like the motherboard is damaged , you may never find the fault, do you have any professional computer training / qualifications ? do you wear an earthing strap when you're touching the inside of the pc? Static electricity can damage components , i.e. Motherboard, sound cards ,Ram chips, etc, I would strongly recommend you cut your losse's and get a qualified PC engineer to sort out your machine.............

 

[zzaxx99]

I think the key factor here is motherboards - I have two identical motherboards in two different cases. It's conceivable that they're both damaged, but both so damaged that they fry the processor? Unlikely, I think.

However, it is possible that the processors have been fried by one of the boards, but not probable, I don't think. Processor 2 was first tried in motherboard A and exhibited the problem straight away. Processor 3 was first tried in motherboard B and exhibited the problem straight away. Unless both motherboards are frying the CPU, it doesn't seem that this should be the problem.

Also, although the machine powers-down after a couple of seconds, this is is after the CPU test in the POST - the diagnostic bracket shows that it passes this test. Now, it could be that the CPUs are damaged in some way that doesn't show up at this stage, but again, Occam would suggest not

 

[zzaxx99]

Interesting idea from the Pcperformance forum

If the heatsink and fan are not correctly installed, including secure thermal pad/grease, the CPU will shut down in a second or two due to overheat. It has a safety cut out. That heatsink really needs to be clipped on good and tight. I've been there.

That's interesting - I didn't think it would cut out that quick for overheating. In the very early days, I had the processor greased and the fan/heatsink clipped on - didn't work then.

Since then, I've just been placing the fan on top of the processor.

I'll have a go a re-greasing the CPU and re-clipping the heatsink, to see if that makes any difference.

Thanks for the idea

Can anyone confirm/deny whether the thermal cut-out really is likely to be this quick?

 

[ChartMan]

I would think that the CPU would go to the great cpu maker in the sky before the overtemp cut in... it's just a thermister underneath the CPU in the middle of the socket.The CPU itself has NO thermal protection. You should never use a fan without thermal grease or thermal "pad" not even for a "quick test". Did you know that the current taken by a CPU is tens of AMPS!!!!

 

[Mayfly]

I'd be tempted to cut my losses on this one. Here's a cheap solution that comes fully assembled and works: http://www.computerfinder.co.uk/asp/showcat.asp?lCatID=4100

You'll be able to use your memory - well, let's hope so - and if you pass the CPU & MB out to those special friends that like to work on this sort of problem, you may get a solution in time.

HTH

Cheers

Mayfly

 

[zzaxx99]

It's Alive!

Turned out that it was thermal cutout - cleaned the CPU surface, put on some thermal grease, attached the fan, switched on..... and it stays on! And the power switch allows it to be switched off again.

Many thanks for all the help and suggestions, folks

 

[Bill G]

It's Alive!

Turned out that it was thermal cutout - cleaned the CPU surface, put on some thermal grease, attached the fan, switched on..... and it stays on! And the power switch allows it to be switched off again.

Many thanks for all the help and suggestions, folks

I'm pleased for you,it`s taken some beating. It's something worth remembering!!!
It starts your New Year off on a good footing.
Bill

 

[zzaxx99]

As of yesterday, I'm running Windows 2003 Server on it - very nice it is too