power supply or something else?

Hi

Help asked for problem with year old self built PC which has suddenly
got a problem with powering on.

SYSTEM:
Seasonic S12 430w power supply, Gigabyte GA-965P DS4 Rev 1 board,
Intel 6300 Core 2 Duo with intel stock fan, Crucial Ballistix
DDR2-667, Antec Solo case with 2 additional 92mm case fans run off
coolmaster aerogate fan controller. 3 Samsung Sata drives and 1 x IDE
DVD writer plus1 x IDE DVD reader. Asus 6200 Geoforce graphics card

PROBLEM:
Press power button, case fans and cpu fan starts and then cpu fan
stops. The power on button flashes and the system powers on and off
repeatedly. CPU fan twitches but doesn't start. Case fans run. The
first time this happened there was an error message re CPU QST fan
control. I set bios to legacy control and then eventually no fan
control when each of these failed to resolve problem.

Anyway back to problem. Switch off power and press power on. Power
button flashes etc. Repeat this many many times. Tried without DVD
drives and with just one disk drive to reduce power load. Also with
CPU fan connected to system fan header rather than cpu fan header. No
change.

Eventually sequence is press power on, cpu and case fans start, cpu
fan continues but power button is still flashing. Leave for a minute
or so and then power off and back on and the system boots up OK.
Once the system has powered on OK it runs without any further problems

Power off and on when the system has been running for a while (i.e is
warm) works perfectly with no problems (although this might be
coincidence).

Any ideas where the problem area is?
Power supply? Cpu fan? or motherboard?
Unfortunately I don't have spares of these to swap and try.

Any help appreciated!
Thanks

Doug

<dh.TakeThisOut@foughill.demon.co.uk> wrote in message
news:it4ve318thkmo9f6mpdh6244kcghur9mbd@4ax.com...
> Hi
>
> Help asked for problem with year old self built PC which has suddenly
> got a problem with powering on.
>
> SYSTEM:
> Seasonic S12 430w power supply, Gigabyte GA-965P DS4 Rev 1 board,
> Intel 6300 Core 2 Duo with intel stock fan, Crucial Ballistix
> DDR2-667, Antec Solo case with 2 additional 92mm case fans run off
> coolmaster aerogate fan controller. 3 Samsung Sata drives and 1 x IDE
> DVD writer plus1 x IDE DVD reader. Asus 6200 Geoforce graphics card
>
> PROBLEM:
> Press power button, case fans and cpu fan starts and then cpu fan
> stops. The power on button flashes and the system powers on and off
> repeatedly. CPU fan twitches but doesn't start. Case fans run. The
> first time this happened there was an error message re CPU QST fan
> control. I set bios to legacy control and then eventually no fan
> control when each of these failed to resolve problem.
>
> Anyway back to problem. Switch off power and press power on. Power
> button flashes etc. Repeat this many many times. Tried without DVD
> drives and with just one disk drive to reduce power load. Also with
> CPU fan connected to system fan header rather than cpu fan header. No
> change.
>
> Eventually sequence is press power on, cpu and case fans start, cpu
> fan continues but power button is still flashing. Leave for a minute
> or so and then power off and back on and the system boots up OK.
> Once the system has powered on OK it runs without any further problems
>
> Power off and on when the system has been running for a while (i.e is
> warm) works perfectly with no problems (although this might be
> coincidence).
>
> Any ideas where the problem area is?
> Power supply? Cpu fan? or motherboard?
> Unfortunately I don't have spares of these to swap and try.
>
> Any help appreciated!
> Thanks
>
> Doug
>

Probability is that it's the PS, and most likely leaky capacitors that once
reaching their load rate (as they warm up through repeated charging by you
presssing the start button) can supply enough current to get the system
running. The most certain method to prove this is to use a multimeter and
measure the voltages with the PS disconnected from the mb and measure the
voltages.

If you aren't familiar as to how to do that then check out this page

http://www.certiguide.com/apfr/cg_apfr_TestinganATXPowerSupply.htm

Additionally you can do a google search for other pages that are available
for testing ATX power supplies. Learning how to do this can be both
interesting and determine whether or not the PS is the problem.

--
Jan Alter
bearpuf.TakeThisOut@verizon.net
or
jalter.TakeThisOut@phila.k12.pa.us