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View Full Version : Kinda no beep, kinda no video...


Mini-Me
03-30-2008, 08:46 PM
Hi.

- ASUS P5GC-MX/1333 motherboard.
- G-Skill 1GB DDR2 RAM module.
- Intel Celeron Dual-Core 1.6GHz CPU.
- 400W ATX PSU.

All parts brand new.

Board sort-of works.

You can fire it up, and it will run sometimes for about 3-4 minutes, then it powers itself off - PSU stops totally. After about 3 seconds, the system re-starts itself, in spite of the power settings indicating it will stay off if the power fails.

System correctly ID's the CPU, and gives one "Happy" single beep at switch on.

I think the PSU is crook, even though it is brand new...

I doubt it is the motherboard, as it is brand new, and gives the "All systems go" single beep when you turn it on, so BIOS must be happy that board is doing everything it should.

Also not really prepared to suspect a brand new Intel CPU - that should not be the cause of the problems.

CPU fansink correctly fitted, and CPU temp is 27'C after about 3 minutes(longest I could run hardware monitor in BIOS before system shut itself off again.)

All IDE, Floppy and SATA drives UNPLUGGED from both the PSU AND the motherboard, to eliminate possible problems here...

I have another PSU(a moderately expensive 500W one), so will plop that in there to test this theroy, but would like to know if others here think I am looking in the right place...

ADDITIONAL: It's not the PSU - with a 520W PSU in there, it does exactly the same thing.
Perhaps the motherboard IS crook?
:rolleyes:

ADDITONAL ADDITIONAL: Hmmm. The plot thickens... Board runs fine out of the case. Obviously does not like being grounded via the mounting holes, to the case itself.

...although most other motherboards are grounded in the same way(via the mounting screws), and they work OK, so not sure what this is about...

I have plenty of nylon washers - I will install some top and bottom of each hole, to isolate the mounting screws electrically from the case, then post back.

Ajmukon
03-30-2008, 09:31 PM
check the pins to the CPU.

sometimes, you can "see" a crooked pin or a misplaced pin

if it is, try another mobo and see what happens.

sassie05
03-31-2008, 12:13 AM
ADDITONAL ADDITIONAL: Hmmm. The plot thickens... Board runs fine out of the case. Obviously does not like being grounded via the mounting holes, to the case itself.

Yep, sounds like a short somewhere.

I have plenty of nylon washers - I will install some top and bottom of each hole, to isolate the mounting screws electrically from the case, then post back.
Sounds like you are on the right track.
Check carefully that all your stand-offs are correctly positioned to the mounting holes on the MOBO.

mjc
03-31-2008, 12:56 AM
Also, look for abnormally long 'tails' on things like capacitors...

There are also times where I've been very tempted to place a sheet of plastic between the motherboard and the 'tray', punching out holes for the mounting screws.

Mini-Me
03-31-2008, 05:01 AM
Yes, this seems to have fixed it(the nylon washers) - board stays going now.
Weird one...
:confused:

jlreich
03-31-2008, 08:02 AM
Probably something that once the board got warm after a few minutes, expanded, made contact and shorted out.

Guess they still include the washers with the case hardware for a reason. :)