Cooling Issues.

[Vormulac]

Hi all,

This is slightly OT for this group, but I get such good advice here I
thought I'd give it a shot.

Last weekend I installed a new processor and grahpics card in my A7N8X-
Deluxe system (XP3200 and 9800XT). Over the last couple of days it's
been behaving oddly with several crashes, so I loaded up Asus probe just
in case, sure enough it instantly started bonging at me as the CPU was
at 76 degrees! The SmartDoctor util with the 9800 said the GPU was in
the high 60s too!

I took the side off my ancient Maplins tower and sure enough the temp
dropped enough to save the bongs (below 72 degrees), but any attempt to
play something, even the gorgeous Ati screensaver coming on, pushed it
back into the danger zone.

I currently have the large mains fan from my desk blowing into the case
giving me a CPU of 53, Motherboard of 25 and Gpu of 50 degrees. This is
clearly not a good thing though. It's only a matter of time before I
kick the fan over for a start...

I'm using the Akasa AK795 heatsink that came with the CPU, with a
coolermaster Aero blower on top of it, with a 60mm case fan blowing
towards it and another 60mm job above the psu as an exhaust. I used
Arctic Silver 5 when I installed the cpu, and the HS looked pretty good
with that copper base. I have a Tagan 480w psu on route to replace my
Enermax 350w and I'm planning a case upgrade at some point, probably
something like a Wavemaster or Praetorian, so hopefully I can replace my
60mm case fans with something bigger, but am I missing something
obvious??
I've built dozens of systems and never had a problem with heat (although
I've never used a cpu or gcard this powerful before).

I would be interested to know what people with similar systems are
running at temp-wise and how they have their cooling arranged. I'm not
sure I'll be going to looking at a vaporchill or watercooled solution
anythime soon though!

Thanks all, I'd be keen to see what you guys have.

 

[Blaedmon]

Youre right, you should be concerned - I have 3 a7n8x-x's with
2500+xpm's@3500+ with copper-based Aero7 using 2 front intake fans, 1 side
intake fan, 1 top exhaust and 1 rear exhaust and the machines are always
icey - never going over 40temp. So somethings very wrong with your system
but I cant really give an idea of what it is. Youre doing everything right.
Possibly do you have ribbon-cables or rounded cables? There could be an
air-circulation dead-zone going on inside the case? Also Ive noticed some
PSU's in the past have been designed to suck and not blow.. which is
retarded - could be adding to your temps? What else... do you have air
conditioning going on? You could always try a different conductive solution?

 

[John Saunders]

I have a Thermaltake Silent Boost and my temp is 38 degrees right
now. My case has a rear 80mm Vantec Stealth slow speed fan sucking
hot air out (which I turn off in winter), and the PSU has a single
low speed 120mm fan at the bottom blowing out through a honeycomb
grill at the back. The ATI 9600XT has a small fan and the Silent
Boost has a slot 80mm fan. No not a lot of fan activity is needed
to get 38 degrees if the forced flow complements natural thermal
flow.

As a first step I would leave the side off the case and disable
all the additional fans. These only have any effect on a closed
box. Once you get the CPU temp right, close the box and enable
the additional fans. If the CPU temp goes way up then you have
the fans wrong.

Also is the thermal paste applied correctly, and does the
heatsink make good contact with the CPU? Try removing it and
see what pattern the thermal paste leaves behind. You should
see very little paste left on the CPU core, with most of it
having been squeezed out the sides. Clean it with isoproyl
alcohol and reapply the paste and remount the heatsink.

Unlike the P4, the small CPU core contact area of the Athlon
needs a heatsink that is able to spread heat away from the
core through the base very quickly. This pretty much means
a solid copper base. Anything aluminium with an embedded
or bonder copper plate is not up to the task with an XP3200.

As for placement and flow direction of additional fans. Don't
try blowing a fan towards the CPU fan. Use those fans to vent
the hot air that collects at the top of the case due to
thermal conduction. Once the hot air is removed the CPU fan
is only able to blow cool air onto the heatsink, and doesn't
need any assistance from other fans.

The rule is that hot air gets sucked out the back of the case
by the PSU fan and any case fans. Do not run any fans mounted
on the back in the wrong direction, you will create an air loop
where hot exhaust air gets sucked back into the box. You can
mount fans on the fron blowing air into the case, but it is
just a waste of power and noise as all tests confirm little or
no benefit from front inlet fans.

 

[Paul]

Hi all,

This is slightly OT for this group, but I get such good advice here I
thought I'd give it a shot.

Last weekend I installed a new processor and grahpics card in my A7N8X-
Deluxe system (XP3200 and 9800XT). Over the last couple of days it's
been behaving oddly with several crashes, so I loaded up Asus probe just
in case, sure enough it instantly started bonging at me as the CPU was
at 76 degrees! The SmartDoctor util with the 9800 said the GPU was in
the high 60s too!

I took the side off my ancient Maplins tower and sure enough the temp
dropped enough to save the bongs (below 72 degrees), but any attempt to
play something, even the gorgeous Ati screensaver coming on, pushed it
back into the danger zone.

I currently have the large mains fan from my desk blowing into the case
giving me a CPU of 53, Motherboard of 25 and Gpu of 50 degrees. This is
clearly not a good thing though. It's only a matter of time before I
kick the fan over for a start...

I'm using the Akasa AK795 heatsink that came with the CPU, with a
coolermaster Aero blower on top of it, with a 60mm case fan blowing
towards it and another 60mm job above the psu as an exhaust. I used
Arctic Silver 5 when I installed the cpu, and the HS looked pretty good
with that copper base. I have a Tagan 480w psu on route to replace my
Enermax 350w and I'm planning a case upgrade at some point, probably
something like a Wavemaster or Praetorian, so hopefully I can replace my
60mm case fans with something bigger, but am I missing something
obvious??
I've built dozens of systems and never had a problem with heat (although
I've never used a cpu or gcard this powerful before).

I would be interested to know what people with similar systems are
running at temp-wise and how they have their cooling arranged. I'm not
sure I'll be going to looking at a vaporchill or watercooled solution
anythime soon though!

Thanks all, I'd be keen to see what you guys have.

1) Checked that heatsink is not rotated 180 degrees ? The contact patch
on the heatsink should line up with the die. That is one error that
sometimes happens.

2) When having temp problems, you should post the CPU temp, case temp,
and room temp. Case should be no warmer than 7C over room temp,
according to an AMD doc. If case is really warm, it will be pretty
hard for the CPU cooler to dump the heat. Like a recent poster had
a case temp of 41C, and that means the CPU HSF has no place to put
the heat.

You mention 60mm fans on your Maplins case, and that strikes me as
not giving you much in the way of airflow. Some cases ship now with
room for a single 120mm fan, and considering you have a 9800XT as
well, more case air should help you.

Something else you may want to check, is run your hand over the
components on the 9800. I bought a 9800Pro 128M, and there are a
couple of wire wound inductors near the top of the card that get
hot when gaming. I found that adding a fan mounted in the adjacent
PCI slot that blows over the face of the 9800, cools it down enough
so I can touch it. (I use the PCI slot screw and a piece of aluminum
angle iron as a mount, then tywrap the fan to the angle iron.)
While it probably isn't an immediate issue, if the core of that thing
is powdered iron, running it so hot that you cannot touch it, would
cause the powdered iron core to "age" and the inductance will change.
The rest of my card seems to be behaving itself - no other hot spots.

Paul

 

[Bx.Cornwell]

Something else you may want to check, is run your hand over the

components on the 9800. I bought a 9800Pro 128M, and there are a
couple of wire wound inductors near the top of the card that get
hot when gaming. I found that adding a fan mounted in the adjacent
PCI slot that blows over the face of the 9800, cools it down enough
so I can touch it. (I use the PCI slot screw and a piece of aluminum
angle iron as a mount, then tywrap the fan to the angle iron.)
While it probably isn't an immediate issue, if the core of that thing
is powdered iron, running it so hot that you cannot touch it, would
cause the powdered iron core to "age" and the inductance will change.
The rest of my card seems to be behaving itself - no other hot spots.

i believe Vantec makes an actual card that plugs into a PCI slot, that has
two fans on it, so rigging up your own design isn't really necessary

 

[_P_e_ar_lALegend]

Il Sat, 17 Jul 2004 23:34:30 +1000, Blaedmon ha scritto:

Youre right, you should be concerned - I have 3 a7n8x-x's with
2500+xpm's@3500+ with copper-based Aero7 using 2 front intake fans, 1 side
intake fan, 1 top exhaust and 1 rear exhaust and the machines are always
icey - never going over 40temp.

Sorry but 40 under heavy load is quietly impossible to believe.

 

[Blaedmon]

Believe it

Il Sat, 17 Jul 2004 23:34:30 +1000, Blaedmon ha scritto:


Sorry but 40 under heavy load is quietly impossible to believe.

 

[Paul]

Il Sat, 17 Jul 2004 23:34:30 +1000, Blaedmon ha scritto:


Sorry but 40 under heavy load is quietly impossible to believe.

That is an Athlon XP-M, as in mobile processor. There are two versions,
one is 35W max power and the other is 45W max power. If you don't
overclock them, and can find a way to "undervolt" them (as the BIOS
will prevent you from dropping the voltage to the spec level), they
will, in fact, run cool. Most people buy mobile Athlon processors
(from Newegg), to overclock them. A few people use mobile processors,
to build ultra-quiet computers, as little cooling is needed if you
volt mod the motherboard for lower voltages, and use a low power
video card like a FX5200 AGP or an equivalent fanless ATI video
card.

Paul

 

[_P_e_ar_lALegend]

Il Sun, 18 Jul 2004 10:42:07 +1000, Blaedmon ha scritto:

Believe it

I still don't: I'm a catholic trained guy, and I'm like St. Thomas: I
would not believe such an issue also if u send me screen shot with that
kind of reading under heavy load.

Also if it's a M version, also if u under volted it

PS: please learn quoting.

 

[Blaedmon]

hehe Apart from me not even saying that 40 was during heavy load, your
argument is simply flawed from the beginning I win.. err.. WE win, so I
guess that means you lose
Seriously, get some experience with (M)obiles. Theyre great chips; more
stable and running cooler. End of discussion.

 

[Vormulac]

Thanks for the advice chaps, I'm going to have a good hard look at my fan
setup and order some better ones in the meantime. I'm certain the HS is
correctly mounted on the cpu though, the step is something I always look
for (I'm paranoid about blowing expensive silicon!)

 

[_P_e_ar_lALegend]

Il Mon, 19 Jul 2004 01:43:22 +1000, Blaedmon ha scritto:

hehe Apart from me not even saying that 40 was during heavy load

Then whats the point???

Mine is 37 when finished booting, then 48 with many background processing
running in the back. It's 51 at full CPU load, solid rock 51.

Then I think my system is perfectly cooling and I think M chip would do
pretty much the same, and I bet your own system would do worst.

Now, end of discussion, and u still haven't learn quoting, how u can think
to cool a system?

 

[Sept1967]

There are only a few "real" ways to help cooling, using air.

Buy a better designed heatsink (pure copper, smaller thinner fins, ect)
And adding more, and/or louder fans.

You could buy a case with a 3g air duct (side air duct that vents cool
outside air directly onto the cpu heatsink fan). I have an mATX case, with
one of these, running a 3G P4, idle temp is 89f (no shit). Full load is
109f. Using a Zalman 7000AlCu heatsink on lowest "silent" setting.
Same PC has an Enermax 365 dual fan power supply, and a single Vantec
"Stealth" exhaust fan, and the system is pretty much silent. Not bad for
3GHz .