Ahhh...didn't spot that the CD etc was getting power...my oversight.

However, as long as the HDD is getting power, then it should spin up if it's not connected to anything else by the ribbon cable. If it's going dead after a moment, then that doesn't sound good for the drive....By "stops after a little activity" though, do you mean that the light goes out? If so, then that's normal until it gets instructions from the MB as long as it keeps spinning...

Silly question, but do you have a multimeter to hand? It's still possible the PSU is the problem if only the 5V lines are working....the HDD and CD usually only tap the 5V supply where as the MB needs the 12V working too...

Assuming no-one openned the case and 'fiddled' then the most likely issue is the CPU fan 'stalled' being dirty and the CPU is now toast.  It DOES happen.

If the CPU fan can be kick-started to run....[flick it with your finger while powered up] then that'll be the culprit....and it's new CPU time...

'IF' some 'friend' has 'fiddled' without your knowledge then ask him/her what 'happened' and why.

So many ways to revert electronics and placky bits to junk-status it ain't funny...

BoXXi - at this point, you ought to have almost nothing left connected, let alone seated correctly...a MB, Processor and RAM connected to the PSU would be the starting point from now...and you might even want to take out the RAM and Processor...not kidding, as a lot of MB's and BIOS will give you a nice series of beeps even without a CPU or RAM...

Yeah...this no beep thing is really annoying me...even if the CPU was dead, dying or indifferent, it would still beep. As a matter of fact, you could take everything out and it would still beep. This is a memory check John (your memory)...didn't these boards have removable Bios chips set in a socket?

yrag....I've had zero post codes from a board which had a dud CPU....pickled by fan.

Perhaps without the CPU some boards 'may' emit a post signal....but not always.

Also....silly Q, but modern boards have a piezo post...older ones will be dead silent if the PC speaker is not connected....and since they are one of the crappiest components....usually some dopey home-solder job....another thing to check...

Paul...you're gettin' pretty old...could be your hearin'

Yes....very likely....and Bryan ain't too young neiva.....so perchance a trip to the Eye and Ear Hospital is in order...

...I'm older then either of you....I'll meet you guys there

You can take off the heat sink and look on the bottom of it to see if you fried the CPU. If the fan stalled thus causing the CPU to burn up, there will be evidence of it.

*thinking...I'm much more used to trying to give support like this over the phone, and being able to go and visit the darn thing if it gets to this stage*

Ahhh, I know...make sure you're holding a big hammer and look mean...it'll keep misbehaving until it knows you're serious, or until it thinks you've given up...

/me goes off to find "The Bigger Hammer"

No evidence of burning anywhere on the cpu......

 

Bryan..I'm sure you did this already, but you did check the power connector from the PSU to the Mobo and make sure both sides are firmly in place...right?

I'm assuming all the instructions above have been tried now, including disconnecting all the turbo/reset switch connections - the reason I ask is that many moons ago, when making a batch of machines for a client, one was dead as a dohdo...and I tried 1001 things before I found out that it was the CASE which was the problem - the reset switch was being constantly pressed, which prevented ANYTHING starting....symptoms which fit yours, and a reset switch could easily have been dislodged or damaged in transit.

Of course, if you've disconnected all the case switches from the MB then this is eleminated...in which case, my next step would be to establish a static free zone, strip the MB and PSU out of the case and set them up on the bench on some insulation. The shorting problems that were already suggested are sometimes only spotted once the MB has been removed.

Ooo..... this is Exciting!

Gary..... yes I checked that.... have tried just about everything  listed above....no joy. i AM concerned that the cpu fan won't work, no matter how much I coax it, that can't have been good for the health of the CPU, must have been running way hot for ages.

Actually, I have a brand new case sitting here, I will swap everything to that tomorrow and see if it cures anything. Can't hurt to try. Have to go to bed now...... 2:30am here....have to be up EARLY!!! thanks for the help guys.....I AM listening and trying everything you suggest.

Heat over time could have crapped it out...do you have somewhere around you can bench it and see if it's alive or dead?

OK Bryan...when you do it just start with the minimum...CPU, one stick of memory and the HD...I wouldn't even put the graphics card in unless you get a beep. If you do, shut it down and slap it in.

....night

2:30? You wooss It's the same time for me, and you have a point...Zzzzzzz

Best of luck with it tomorrow...though, it is sounding like a poached CPU...it was much easier diagnosing things like this when I had a workshop full of spares to swap in...this all becomes glorified mechano then...just swap bits till it works then charge the customer for the bit you swapped last

yrag - don't even connect the HDD to start with...there's no need for that to get the MB/BIOS starting up.

Actually...I'm not connecting anything and I think Bryan is suave enough to know if he can't move forward to go back wards

Aargh....'Meccano' [ ] is less of a pain than Computers....[had the former for about 45 years]...

The CPU may not show frying signs.....that's not always the case, either...

If the fan refuses to spin then it's not looking good for your MoBo....[or the fan itself or the PSU supply to the MoBo]....then there was the dope with the 110/230 volt switchable PSU......who thought it'd be 'interesting' to switch to 110 [while it was running]......just managed to salvage the case.....everything in it was nouveau-junk...

Jafo, you run 230 down there? My systems runs on 110.

My memory isn't what it use to be, but I seem to remember some boards (the better ones, which Abit would certainly be one) would not boot or beep if the CPU fan was plugged into the three pin connector on the Mobo and was not running...not sure what it would do if you just pulled the plug....a short boot test won't hurt the CPU, but it might still detect it as a bad fan until a new one is thrown in....

...I don't know....relying on my memory is not a save bet

...wouldn't it be a chuckle if all this is over a dead fan

Just a note, don't necessarily rule out the Power Supply being bad. I had a system that did pretty much what you describe (brief bit of lights, etc., from the drives, no post, no boot), hooked up another PS, and all was working again.

Another thing to try that I've seen work for a similar problem is to completely clear the CMOS memory associated with the BIOS (remove the battery and temporarily short the battery connections, replace battery; additionally, quite a few motherboards have a cmos clear jumper position, which you'll see somewhere near the battery, jumper that for a minute and undo).

I consider these low probability solutions, especially considering what has already been suggested (and you have tried), but I have seen both of these methods fix a couple of my PCs that were exhibiting symptoms similar to yours.

Good Luck!