S
Steve Sr.
I just put together a P4 based system in an Antec 1080 case. The case
comes with a True Power 430 watt power supply. The power supply has a
120mm fan on the bottom that draws air into the bottom of the supply
and an 80mm fan that exhausts air out the back of the case. Sthe power
supply also has an output to power case fans in parallel with the
one(s) in the PS and a fan speed monitoting output to feed the
motherboard.
In addition the case has room for 5 more fans, 2 in the lower front,
two in the middle of the rear and one on the side cover over the video
card. In this application I have the two in front and the highest one
in the rear populated.
Since heat rises I have tried to turn the case into a chimney to aid
the fans as much as possible. This draws cool air in the lower front
and exhausts hot air out the top rear. I have blocked off the other 2
unused fan openings so that convection doesn't get short circuited.
I ran the computer like this overnight running Memtest86 and the next
morning I noted CPU and MB temperatures of 46/33 degrees C
respectivly. I also noted that monitored PS fan was running about 1605
RPM.
During this test I noticed that the case and all of the components in
the case got warm to the touch especially the CD drives in the top of
the case. This got me to thinking about the source of a lot of this
heat. It was the power supply itself!
The existing fan arrangement in the PS with a big one drawing in and
smaller one drawing out was causing the the power supply heat to be
dumped back into the case via the vent holes in the power supply!
That heat should be getting dumped *outside* the case and not back
into it. In order to make this happen I tried an experiment and
covered all of the vent holes in the PS with clear packing tape. This
would force a single path for air through the PS.
I ran the same experiment and in the morning noted no change in the
CPU / MB temperatures. I surmise that the MB temperature is heavily
influenced by exhaust from the CPU fan. The real surprise is that the
top of the case and all of the other components inside it were now
cool to the touch!
Some may wonder that this arrangement would cause the PS to overheat.
I considered this possibility and was careful to monitor the PS fan
speed early during the test. When I didn't detect a marked increase in
speed I let the test run overnight. In the morning the PS fan speed
was only 1695 RPM or about 5.6% higher which indicated that the PS was
not appreciably hotter than when it was sucking recirculated hot air
inside the case.
Comments? Has anybody else ever tried this?
Regards,
Steve
comes with a True Power 430 watt power supply. The power supply has a
120mm fan on the bottom that draws air into the bottom of the supply
and an 80mm fan that exhausts air out the back of the case. Sthe power
supply also has an output to power case fans in parallel with the
one(s) in the PS and a fan speed monitoting output to feed the
motherboard.
In addition the case has room for 5 more fans, 2 in the lower front,
two in the middle of the rear and one on the side cover over the video
card. In this application I have the two in front and the highest one
in the rear populated.
Since heat rises I have tried to turn the case into a chimney to aid
the fans as much as possible. This draws cool air in the lower front
and exhausts hot air out the top rear. I have blocked off the other 2
unused fan openings so that convection doesn't get short circuited.
I ran the computer like this overnight running Memtest86 and the next
morning I noted CPU and MB temperatures of 46/33 degrees C
respectivly. I also noted that monitored PS fan was running about 1605
RPM.
During this test I noticed that the case and all of the components in
the case got warm to the touch especially the CD drives in the top of
the case. This got me to thinking about the source of a lot of this
heat. It was the power supply itself!
The existing fan arrangement in the PS with a big one drawing in and
smaller one drawing out was causing the the power supply heat to be
dumped back into the case via the vent holes in the power supply!
That heat should be getting dumped *outside* the case and not back
into it. In order to make this happen I tried an experiment and
covered all of the vent holes in the PS with clear packing tape. This
would force a single path for air through the PS.
I ran the same experiment and in the morning noted no change in the
CPU / MB temperatures. I surmise that the MB temperature is heavily
influenced by exhaust from the CPU fan. The real surprise is that the
top of the case and all of the other components inside it were now
cool to the touch!
Some may wonder that this arrangement would cause the PS to overheat.
I considered this possibility and was careful to monitor the PS fan
speed early during the test. When I didn't detect a marked increase in
speed I let the test run overnight. In the morning the PS fan speed
was only 1695 RPM or about 5.6% higher which indicated that the PS was
not appreciably hotter than when it was sucking recirculated hot air
inside the case.
Comments? Has anybody else ever tried this?
Regards,
Steve
