I'm running an old Athlon 1200 CPU in a fairly new (1yr old) SiS748
chipset socket A board (an ASRock K7S8XE+, to be precise). It's been
OCd to 1300 (200x6.5) for a year without probs. 1 256Mb stick of DDR400
RAM, one 120Gb SATA HD, one CDRW.

About a month ago it started shutting down randomly - anywhere between
10mins and 48 hours after booting. Not a total shutdown - fans and LEDs
would stay on, but drives and video would suddenly stop. No way to
resurrect it without power cycling.

I figured it was the PSU - once upon a time I put 240v into that PSU
when it was set to 110v, so I guess it may have been damaged, even
though it seems fine thanks to fused plugs! So I bought a brand new ATX
PSU and put it in.

The same thing still happens, but the symptoms are now slightly
different with the new PSU - instead of the fans and LEDs staying on,
the system shuts down completely - total power off. (I do have to power
cycle the PSU before it will come back on though, it's not just a
matter of pressing the power button.)

Assuming the brand new PSU is not faulty, what's the most likely cause?
Is the CPU dying? (The monitoring software shows totally stable CPU
temp and fan speed while the system is up.) The mainboard? The RAM? The
video card? (An old GeForce2MX400) I don't understand what would bring
the whole system down, and it will be painful to replace every piece
sequentially!

Grateful for any tips, if anyone's seen anything like this before.

CC

On 27 Aug 2005 07:06:33 -0700, "magnate" <(E-Mail Removed)>
wrote:

>I'm running an old Athlon 1200 CPU in a fairly new (1yr old) SiS748
>chipset socket A board (an ASRock K7S8XE+, to be precise). It's been
>OCd to 1300 (200x6.5) for a year without probs. 1 256Mb stick of DDR400
>RAM, one 120Gb SATA HD, one CDRW.
>
>About a month ago it started shutting down randomly - anywhere between
>10mins and 48 hours after booting. Not a total shutdown - fans and LEDs
>would stay on, but drives and video would suddenly stop. No way to
>resurrect it without power cycling.
>
>I figured it was the PSU - once upon a time I put 240v into that PSU
>when it was set to 110v, so I guess it may have been damaged, even
>though it seems fine thanks to fused plugs! So I bought a brand new ATX
>PSU and put it in.
>
>The same thing still happens, but the symptoms are now slightly
>different with the new PSU - instead of the fans and LEDs staying on,
>the system shuts down completely - total power off. (I do have to power
>cycle the PSU before it will come back on though, it's not just a
>matter of pressing the power button.)
>
>Assuming the brand new PSU is not faulty, what's the most likely cause?
>Is the CPU dying? (The monitoring software shows totally stable CPU
>temp and fan speed while the system is up.) The mainboard? The RAM? The
>video card? (An old GeForce2MX400) I don't understand what would bring
>the whole system down, and it will be painful to replace every piece
>sequentially!

The most common causes of shutdowns like this are the power supply and
motherboard. Since you've already swapped power supplies, I would say
that it's most likely you're motherboard. That being said though,
just about any electrical component could cause this, but system board
is most common.

One thing I would suggest is to visually inspect all the capacitors on
the system board. See if any of them are bulging and/or leaking such
as the capacitors listed at:

www.badcaps.net


I don't know if you're board is one of the MANY motherboards that were
affected by this issue, but it's worth having a look at the caps, just
in case.

-------------
Tony Hill
hilla <underscore> 20 <at> yahoo <dot> ca