Need a bit of advice with cooling PWM/SYS on an Abit an8-sli

Artheas · 26 Apr 2006 at 22:40

This board uses passive cooling for the mobo chipset, as shown here - http://www.bit-tech.net/hardware/2005/12/01/abit_an8_sli/2.html

Mine tends to get above 50 degrees when under load, and even though i've heard they can go pretty high without damage, i'd rather have it a bit cooler.
The exhaust area is above the CPU fan, and my arctic freezer pro doesnt really blow any air out of the Q-OTES exhaust.

When i was messing about with my system and it was out of the case, having a 120mm fan blowing over the exhaust cooled temps by about 5 degrees. Now my problem is how i'm going to do that when everything is in the case.
Having a fan inside blowing air out the exhaust is the most obvious, but it would need to be a pathetic 40mm fan for it to fit in - that's if i can find a way of suspending it under the PSU.
My other option is to mount a fan outside the case, 'sucking' air out if you will. Unfortunately, the air a fan blows does not equal the amount it sucks in perpendicular to the fan, so this may not help much.
The only other option i can think of is to have a fan blowing INTO the case via the q-OTES exhaust, and hope that the cpu fan will redirect the hot air out of the case exhaust.
If i were to do this, i'd then have to decide whether to use a 120mm fan, or 2 40mm fans side by side, which covers the exhaust perfectly.

Any ideas/tips? Especially on how to have fans inside the case where you're not really meant to have fans =/ (no superglue please!)

Dutch Guy · 27 Apr 2006 at 10:05

Artheas said:
Any ideas/tips? Especially on how to have fans inside the case where you're not really meant to have fans =/ (no superglue please!)

- Do not use 40mm fans, they whine and have very low airflow.
- You have to find a way to mount a quiet 80mm fan inside the case blowing onto the OTES and out the back, maybe double sided tape on the bottom of the PSU with the fan pointing towards the OTES?

TaKeN · 27 Apr 2006 at 11:13

Put more case fans in

Panaflo's are the best imo,

My PWM Says its @ 35oc When im playing BF2

Thats the uGuru Front Panel Reading

boosfuk · 27 Apr 2006 at 12:06

I had similar thoughts with my AN8 Ultra but it does not measure the chipset temp (only PWM) so don't know if I have a heat problem. I also run an AC Pro cpu cooler. I did mount a 80mm fan on a PCI slot blank (drilled holes and used cable ties) and put it in the first PCI slot in case - this sent air perpendicular to the OTES radiator so might have helped a little (but did point at PWM heatsinks). It is difficult to mount a fan inside and above because the air would get sucked out by the exhaust fan before reaching the OTES. I was also thinking of suspending a 92/120mm fan above (at a distance - not mounted!) the chipset itself using a Zalman bracket and use it to cool it a little directly in addition to help the graphics card.
I have heard that the chipset does not get too hot anyway so it should not really be a problem - also it might be better as well to remove the OTES heatsink on the chip and replace the pad with some thermal paste - one person on the ABIT boards posted that his by default hardly made contact and using AS5 reduced his crashing problems presumably due to high temps. I might do this next time board is out of the case.
Anybody and other thoughts?

Artheas · 27 Apr 2006 at 12:55

I would add a few case fans if i could, but my eclipse-62 only has space for 2

I dont actually know the difference between SYS and PWM, but it was PWM that went down when i blew a fan over the OTES exhaust, whereas if i blew a fan over the heatsink/chipset next to the graphics card, it made no difference to temperatures.

I'm buying some cables and fans atm, so when i change them, that'll give me a chance to try different things.
I'll try remounting the chipset heatsink with some AS5 and see what that does, and i'll use the double sided tape from the vf900 to try and mount an 80mm fan under the PSU. I'll probably also try an 80/120mm outside the case blowing in, hoping that the PSU fan blows the hot air into the path of the CPU airflow lol..

When i get the stuff, i'll post the results and some pics for anyone thats interested. That's if the second camera i've ordered arrives.. *mumbles something about stupid ebayers*

boosfuk · 27 Apr 2006 at 13:02

I dont actually know the difference between SYS and PWM, but it was PWM that went down when i blew a fan over the OTES exhaust, whereas if i blew a fan over the heatsink/chipset next to the graphics card, it made no difference to temperatures.

As I understand it:

SYS: case temperature i.e. ambient at motherboard level
PWM: (PWMIC) voltage regulators. These are between the CPU and the OTES exhaust (under/by the 2 heatsinks). So not surprising that the temp goes down when you blow a fan there and does not when you blow it on the chipset heatsink. This is nothing to do with the chipset/OTES temp.
The PWM temp can go very high with no problem (to 80/90 I think) so 50 is no real problem. Also the AC Pro cooler does provide some cooling/airflow here.

N.B. if you do remove pad on chipset heatsink then make sure you only remove the central pad and not the outside foam shim as well (which stabilises the heatsink so you can screw it back down easily). It will e obvious when you remove it.

Let us know how you get on.