9800 GX2 + GA-EP31-DS3L = overheating southbridge?

[edwina5000]

Hello all.

I have just got myself a 9800 GX2 off ebay (I know, I know) and it seems to run fine. Right up until I start gaming, that is, when it freezes within a few seconds.

I'm pretty sure that this is a problem with my southbridge overheating. The GPUs never go above 75 and my CPU stays below 70 (which is normal for my OCed E4300), but games or OCCT GPU test start to stutter a bit then freeze after a few seconds. The card is still working (still got a picture) but I have to reboot.

I tried taking the side off my case and pointing an 80mm fan at the southbridge and that got me playing MW2 for about 30 minutes (at a nice 50FPS) before stuttering got more and more pronounced ... then it crashed.

With my board the southbridge is right under the monster card (http://www.infoxmatica.com/catalogo/images/intel-gigabyte-ep3.jpg), and I have only one PCI-E slot to choose from.

I tried putting everything back to default in the BIOS, but the CPU then bottlenecks the GPU so much that it games are unplayable. Also tried underclocking the GPU, but that didn't make much difference.

Anyone got any bright ideas for cooling the southbridge before I sell my GX2 on? I don't think there is space to fit even a small active cooling thingummy on top, under the GX2. My case doesn't have great cooling, but in any case it feels like even the best case cooling would fail to get to that very specific area with enough air to cool it properly.

Failing that, do you think my diagnosis is correct?

Many thanks in advance.

My rig:
Corsair 650TX
GA-EP31-DS3L rev 1.0
Asus 9800 GX2
E4300 @ 3GHz
4Gb Corsair TWIN2X4096-6400C

 

[wa1]

I have GA 965P DS3 GigaByte motherboard, no matter what the room temps, my south or north bridge temp (HW Monitor) is always around 47'C-50'C. Is that fan would help?

 

[wa1]

Thanks, ct1615...

 

[edwina5000]

A little delayed, but worth posting my findings back here.

Firstly, thanks to ct1615 for this:

"Gigabyte boards are notorious for having hot northbridges (around 80c) but i have never heard of the southbridge having heat issues on them."

It seemed obvious to me that the southbridge was the overheating one but this comment made me switch my focus to the northbridge. Turns out that was what was overheating. Not a problem I could overcome permanently without much better case cooling so in the end I gave up and sold the 9800 GX2 on.

Thanks for the advice all. Hope this helps somebody, in any case.