View Full Version : Here's one for techs

07-12-2010, 09:41 AM
A customer brought their two year old computer in for warranty repair yesterday.
It has been working fine for those two years but has now failed.
It powers on but nothing appears on screen, then turns off after about 5 seconds. (This is the same thing that happens if I power on the computer without a CPU)
I did the usual checks on PSU, RAM etc and tried other known goods ones but it still faulted.
I then removed the AMD 5200+ CPU and put it into another computer and it works fine.
So I then put an AMD 3800+ CPU into the customers computer and it works fine also.

So which part is faulty? The CPU or the mainboard?

My money is on the mainboard (Asus) and I am going to try a BIOS reset and also a BIOS update if there is one available.
Will let you know what happens.

07-12-2010, 09:42 AM
I would say intermittent fault with the motherboard too.

I also had as Asus board (M2N32 SLI Deluxe) which had this exact same issue. 3 year warranty ftw.

07-12-2010, 11:38 AM
Ditto -- My money would be on the Motherboard faulty.

Doing one right at the moment actually,its a very similar to what you describe.

Just finished putting it together, and its installing windows as I have lunch.

07-12-2010, 01:59 PM
So I then put an AMD 3800+ CPU into the customers computer and it works fine also.

Motherboard if it wasn't the usual - HSF not on properly, hot etc

07-12-2010, 03:38 PM
Looks like it is the mainboard.
A BIOS update and reset with the jumper made no difference with the 5200+ CPU.

07-12-2010, 05:11 PM
Motherboard if it wasn't the usual - HSF not on properly, hot etc

Yeah, I'm wondering if it could be heat / fan sensor issues. Maybe, just maybe it was failing to detect the CPU fan speed and was going into a self-protect shutdown.

I'd give the original mix of mobo and cpu another go together and see if simply reseating things have sorted it out.

I'd expect that CPU to generate a fair bit of heat, so maybe it, or it's mounting on the mobo has been cooked at some time.

07-12-2010, 06:08 PM
The mainboard posts and the computer boots fine with the same fan and the AMD 3800+ CPU.
As soon as I put the 5200+ CPU back in it powers up for a few seconds then powers off.
Removed and reseated the 5200+ CPU about 5-6 times now with no difference.
The symptoms are as if the mainboard is not detecting a CPU at all, which I tested as well.

07-12-2010, 09:19 PM
This is one of those problems when having an HP (or such) warranty comes in really handy :D

07-12-2010, 10:08 PM
Dontcha love these ones?

Does the 5200 draw more current? If it does, maybe there are cap problems around the cpu on the mobo?? Or something!!!

08-12-2010, 06:43 AM
I still wonder about the PSU.

I’m wondering if the 5200 is drawing more current and the “Power Made Good” circuitry is coming into play.

Personally, I’d be trying a higher rated PSU and if that didn’t do the trick I’d be guessing Motherboard along with everyone else. :2cents:

08-12-2010, 09:19 AM
The mainboard posts .

Doesn't matter. RMA it.

09-12-2010, 01:06 AM
Mainboard has gone back to Synnex :D