Help with PSU Please

[Cyberdog]

Hi,
I have a Q-Tec 550WP Dual Fan Gold running an Asus A7N8X - E Deluxe
M/B. The computer has started just shutting down for no reason.
Everything has been changed except the PSU. What I want to know is,
does it matter which way up you install the power unit.Thanks

 

[Paul]

Hi,
I have a Q-Tec 550WP Dual Fan Gold running an Asus A7N8X - E Deluxe
M/B. The computer has started just shutting down for no reason.
Everything has been changed except the PSU. What I want to know is,
does it matter which way up you install the power unit.Thanks

I think I would want the fan facing down in the case. It is supposed
to pull air from above the CPU and exhaust out the back of the
computer case. At least, the fan should not be facing the top of the
computer case, as that would make the airflow harder to attain.

I found a sample picture of the PSU here:

http://www.pctuner.net/php/Articoli/Articolo.php?ID=226&PAG=2&lang=ita

It could be the PSU is going bad.

Or, it could be that the heatsink on the CPU is rotated 180 degrees
from the correct orientation. The contact patch on the heatsink
only lines up with the CPU die correctly, with one orientation
of the heatsink. If the heatsink is rotated, only part of the
silicon die touches metal, so the silicon die has radically
different temperatures on either end of it. That could
be triggering Asus COP (CPU overheat protection), as the eight
pin chip monitoring the diode voltage on the CPU die will trip
if it thinks the temp is too high. That would result in shutdown
without warning.

HTH,
Paul

 

[Chris Catt]

Hi, well if the fan on the PSU is facing up instead of down your PSU might
be overheating....
ChrisC

 

[Cyberdog]

I think I would want the fan facing down in the case. It is supposed
to pull air from above the CPU and exhaust out the back of the
computer case. At least, the fan should not be facing the top of the
computer case, as that would make the airflow harder to attain.

I found a sample picture of the PSU here:

http://www.pctuner.net/php/Articoli/Articolo.php?ID=226&PAG=2&lang=ita

It could be the PSU is going bad.

Or, it could be that the heatsink on the CPU is rotated 180 degrees
from the correct orientation. The contact patch on the heatsink
only lines up with the CPU die correctly, with one orientation
of the heatsink. If the heatsink is rotated, only part of the
silicon die touches metal, so the silicon die has radically
different temperatures on either end of it. That could
be triggering Asus COP (CPU overheat protection), as the eight
pin chip monitoring the diode voltage on the CPU die will trip
if it thinks the temp is too high. That would result in shutdown
without warning.

Hi Paul,
Thanks for that. I do have the PSU installed like you say, with the fan
facing down onto the processor. However every picture of this PSU shows
it the other way up ( maybe only to show the other fan). The heat sink
is the correct way around as the cutout fits perfectly over the raised
edge of the processor holder.Also the processor temp is showing between
40C - 41C, never any higher. Today is turned off three times after
being on for no longer than five to ten minuets. However the next start
was ok and it has now been running continually for three hours. I have
changed everything except the heat sink and the PSU. Thanks for your
help.