Ticking and Powering Off

My PC has been behaving very well for the last two and a half years, working
constantly, day and night. Very recently it developed a strange ticking
noise when I was operating it. The tick is quite sharp and soft, like an
electrical spark from a comb. First it seemed like moving the mouse caused
the ticking, but I found out that it also ticked when the scheduled tasks
were launched. It was audible also when the speakers were disconnected.

Soft ticking is not such a big deal, and since the machine functioned fine
otherwise, I made no big deal of it. Now, however, it has started to power
off spontaneously. The fans and disks stop immediately, the screen goes
blank. The 'mains' LED on the motherboard stays on. Hitting the power button
doesn't start it back up. Unplugging and replugging resets the computer to
normal operation, although the ticks start up shortly after boot.

Some exploration of the box suggests that the ticking must come either from
one corner of the mobo (where all the cables come in) or from the PSU (which
is neither hot nor filthy).

All fans spin nicely, the temperatures do no strange things, the voltages
also stay within limits during operation.

Any clues? My prime suspect thus far is the PSU, but I'm loath to open it
needlessly (voiding sticker).

My system:
Asus P5GD1
AOpen 250 Watt power supply
P4 3.0 GHz socket 775
3 WD disks
NVidia 6200 (or something)

On Mon, 03 Sep 2007 04:36:27 +0200, "I.C. Koets"
wrote:

My PC has been behaving very well for the last two and a half years, working
constantly, day and night. Very recently it developed a strange ticking
noise when I was operating it. The tick is quite sharp and soft, like an
electrical spark from a comb. First it seemed like moving the mouse caused
the ticking, but I found out that it also ticked when the scheduled tasks
were launched. It was audible also when the speakers were disconnected.

Soft ticking is not such a big deal, and since the machine functioned fine
otherwise, I made no big deal of it. Now, however, it has started to power
off spontaneously. The fans and disks stop immediately, the screen goes
blank. The 'mains' LED on the motherboard stays on. Hitting the power button
doesn't start it back up. Unplugging and replugging resets the computer to
normal operation, although the ticks start up shortly after boot.

Some exploration of the box suggests that the ticking must come either from
one corner of the mobo (where all the cables come in) or from the PSU (which
is neither hot nor filthy).

All fans spin nicely, the temperatures do no strange things, the voltages
also stay within limits during operation.

Any clues? My prime suspect thus far is the PSU, but I'm loath to open it
needlessly (voiding sticker).

My system:
Asus P5GD1
AOpen 250 Watt power supply
P4 3.0 GHz socket 775
3 WD disks
NVidia 6200 (or something)

This does coincide with a typical PSU failure-in-progress.
You might inspect the capacitors on your motherboard, if
some have vented that can result in a problem for the PSU to
operate properly, but since it is only 250W it was already a
candidate for replacement, better to do so before it fully
fails rather than later. The symptoms are most common from
it being purely a PSU failure and having to unplug it is a
sign the PSU's safety shutdown circuit was triggered.

I doubt you have a warranty on this PSU that is still valid
after 2 years. If there is no warranty anymore, there is no
issue of voiding warranty by opening it.

If you open it, leave it unplugged from AC for several
minutes before doing so. However, unless you find vented
capacitors inside, it is not likely to be worth repairing
because as a 250W PSU, it was not sufficient capacity for
your system and would be expected to die an early death due
to running at the edge of it's capability. Burn a candle at
both ends and it won't last as long.

I suggest a replacement PSU of at least 350W, a trusted name
brand rated for at least 18A of 12V current. If this is a
mATX instead of full ATX PSU, you may have to accept a lower
wattage than 350W and end up having to replace it again,
every so often, because these parts in the system are a bit
too much of a load for a typical mATX PSU.

If you feel it is likely you might want to reuse a
replacement PSU with other (motherboard, CPU, video card)
upgrades in the future, you might even consider something a
bit higher than 350W. Although the system needs nothing
more now, that will make it a lot more likey that any future
parts' current needs are covered, plus as briefly mentioned
above, running a higher wattage PSU at a lesser % of it's
total capability will tend to make it last longer - so long
as it was a decent quality unit rather than an overrated
generic.

kony wrote:

On Mon, 03 Sep 2007 04:36:27 +0200, "I.C. Koets"
wrote:

My PC has been behaving very well for the last two and a half years, working
constantly, day and night. Very recently it developed a strange ticking
noise when I was operating it. The tick is quite sharp and soft, like an
electrical spark from a comb. First it seemed like moving the mouse caused
the ticking, but I found out that it also ticked when the scheduled tasks
were launched. It was audible also when the speakers were disconnected.

Soft ticking is not such a big deal, and since the machine functioned fine
otherwise, I made no big deal of it. Now, however, it has started to power
off spontaneously. The fans and disks stop immediately, the screen goes
blank. The 'mains' LED on the motherboard stays on. Hitting the power button
doesn't start it back up. Unplugging and replugging resets the computer to
normal operation, although the ticks start up shortly after boot.

Some exploration of the box suggests that the ticking must come either from
one corner of the mobo (where all the cables come in) or from the PSU (which
is neither hot nor filthy).

All fans spin nicely, the temperatures do no strange things, the voltages
also stay within limits during operation.

Any clues? My prime suspect thus far is the PSU, but I'm loath to open it
needlessly (voiding sticker).

My system:
Asus P5GD1
AOpen 250 Watt power supply
P4 3.0 GHz socket 775
3 WD disks
NVidia 6200 (or something)

This does coincide with a typical PSU failure-in-progress.
You might inspect the capacitors on your motherboard, if
some have vented that can result in a problem for the PSU to
operate properly, but since it is only 250W it was already a
candidate for replacement, better to do so before it fully
fails rather than later. The symptoms are most common from
it being purely a PSU failure and having to unplug it is a
sign the PSU's safety shutdown circuit was triggered.

I doubt you have a warranty on this PSU that is still valid
after 2 years. If there is no warranty anymore, there is no
issue of voiding warranty by opening it.

If you open it, leave it unplugged from AC for several
minutes before doing so. However, unless you find vented
capacitors inside, it is not likely to be worth repairing
because as a 250W PSU, it was not sufficient capacity for
your system and would be expected to die an early death due
to running at the edge of it's capability. Burn a candle at
both ends and it won't last as long.

I suggest a replacement PSU of at least 350W, a trusted name
brand rated for at least 18A of 12V current. If this is a
mATX instead of full ATX PSU, you may have to accept a lower
wattage than 350W and end up having to replace it again,
every so often, because these parts in the system are a bit
too much of a load for a typical mATX PSU.

If you feel it is likely you might want to reuse a
replacement PSU with other (motherboard, CPU, video card)
upgrades in the future, you might even consider something a
bit higher than 350W. Although the system needs nothing
more now, that will make it a lot more likey that any future
parts' current needs are covered, plus as briefly mentioned
above, running a higher wattage PSU at a lesser % of it's
total capability will tend to make it last longer - so long
as it was a decent quality unit rather than an overrated
generic.

I just put in a new 650 W PSU. Problem hasn't reoccurred. Now to see what I
can salvage about the old one.

Thanks!