Current northbridge chips with heatspreader?

Tzupy · Post by **Tzupy** » Fri Feb 06, 2009 10:24 am

I'd like to know which of the current northbridges (AM2+ and Skt775), since the southbridges use little power anyway, have a heatspreader (aren't naked).

I found out that keeping a 45W CPU cool with low airflow is easy when using a Ninja2 with backplate, but I can't drop the case fan rpm too much without chipset temps going up.
That's on a Gigabyte 78GM-S2H, and I'm not using the integrated graphics. The northbridge heatsink is comparable with the old NB47J (not NBF), and it runs hot.
At low load, like now, with the case fan in my P150 at 800 rpm, it reaches 60 degrees. When gaming, with case fan at 1,000 rpm (noisy!) it still goes over 65 degrees.
Since I'd like to use for the case fan (Slipstream) only 600 rpm at low load and 800 rpm when gaming, the chipset temps would probably go over 70 degrees.
Temperatures are measured by a thermal probe touching the northbridge heatsink. I wanted to replace the stock heatsink with a NBF47J, but I discovered the chip is naked, less than 1 cm2. I am obviously picky about chipset temps, since my previous mobo died probably from overheating (an area had bloated capacitors and yellow traces).
And the stock heatsink has a shim apparently glued to it, I couldn't find a suitable shim to put on the NBF47J, also the mounting holes were quite far apart, so I ended up putting the stock heatsink back.

I plan to get a different motherboard in the near future, with a northbridge that HAS A HEATSPREADER. Please advise, thank you.
PS. It may be an Intel mobo, I can switch again. I plan to use on it a Thermalright HR-05 IFX with bolt-through mounting.

JamieG · Post by **JamieG** » Fri Feb 06, 2009 2:34 pm

I've got a Gigabyte 780G GA-MA78GM-S2H in my HTPC.

With a bit of bending of one of the mounting clips, I managed to mount a Thermalright HR-05 IFX on the Northbridge.

I'm not sure how secure it is though

. As the motherboard is sitting horizontal in my HTPC it's slightly less of a concern to me. If you're trying to do this in a P150 with a vertically mounted motherboard, I'd be more hesitant though.

(Sorry, no pics of my system as I don't have a proper camera ...)

psiu · Post by **psiu** » Fri Feb 06, 2009 3:21 pm

Are you having problems relating to the overheating?
The previous problem sounds less like overheating than a symptom of a motherboard with a batch of failed capacitors.

Tzupy · Post by **Tzupy** » Sat Feb 07, 2009 4:49 am

@jamieG: If I would use the mobo horizontally, then I wouldn't have hesitated to put any heatsink on the northbridge with thermal epoxy.
@psiu: No, I don't have any problems now, since I run the case fan at 1,000 rpm when gaming, but I could have if I ran the case fan lower.
The dead mobo had all solid capacitors, and all which bloated are south of the memory slots, where there are a few naked mosfets.

Regarding the current mobo, is there any trick to lower the power draw of the 780G northbridge, when not using the integrated graphics?

Mariner · Post by **Mariner** » Sat Feb 07, 2009 5:48 am

Personally, I wouldn't be too worried with the NB temps you are seeing. I understand that these modern Northbridge chips are specced to run at very high temperatures (similar to the discrete GPUs from AMD/NVidia) and this is why very few of the Northbridge chips have active cooling.

I don't think you'll have any problems but, of course, if adding extra cooling makes you feel better you should go right ahead with it!

psiu · Post by **psiu** » Sat Feb 07, 2009 12:02 pm

Don't see what case you have, but perhaps the simplest would be mounting a slow Nexus or Slipstream inside near the motherboard video area. Just a bit more airflow would help those components and it would be buried enough you shouldn't hear it.