MA-785GT-UD3H NorthBridge Temps too high?

[psyko]

Hi,

I own a MA-785GT-UD3H mobo with a 555BE. My case is an In Win Dragon Rider, which has an awesome thermal performance. My CPU idles around room temp +1ºC and peaks around 38-40ºC under prime95 load on summer, with stock heatsink/fan. I'm saying all that to avoid the classic answer "low case airflow".

At stock clocks, my Motherboard temp shows around 25-32ºC idle (depending if its summer/winter and time since last dust cleaning) and goes up to 52-65ºC with prime95 load (depending if its summer/winter and time since last dust cleaning), which considering the good airflow of my case, it seems too high.

-First of all, What is the max temp recommended for the NB chipset? Is it a general value for every NB, is it chipset specific or chipset+mobo manufacturer specific?

-I've searched many times information about this and I have read many times people saying NB chipsets can run very high temperatures because they are regular silicon chips, instead of germanium dopped ones which are more sensible to high temps, allowing them to safely operate over 80ºC, even at 95-105ºC with just a small lifespan drop and they get destroyed around 125ºC. Is that information true?

-Another important thing is that the 785G chipset has an integrated GPU, which I'm not using (disabled). Maybe because of its specific design that it runs hotter than a normal NB (one without a GPU on it), considering that HD4000 series can operate in the 70-90ºC range and I personally have a friend running his HD4890 around 95ºC for a couple of years and its still working fine. Maybe that is what happens?

-Or may it be the sensor?, that it is not working fine...
In this case, is there any solution? (like applying an offset or finding a relation with another temp that increase proportionally or...)

Thanks in advance for your help :)

[Vinster]

I just build a AMD 970 series for my folks and found the NB temps to very high as well idle temps were like 60 degrees. I added a tiny 40x40mm 4000RPM fan to the heatsink that helped my temps by nearly 10 degrees.

I left it at that.

Vin

[psyko]

I guess I have found the problem indirectly :P

I bought a new CPU cooler (Mugen 3 rev B) to push my unlocked CPU to over 4 GHz (still working on it). After mounting it, I started windows and run some test to see how the cooler was doing. My surprise is that the core temps were not the only ones that dropped, the motherboard temperature also went down.

Now motherboard temps are ambient + 3-5ºC on idle and 42-46ºC under prime95 load.

I'm saying this because I think it might help others:

In my opinion, what was happening is that the AMD stock cooler was pushing hot air from the CPU to the NB chipset because of its blowing direction (perpendicular to the motherboard, so hot air spreads over the components 360º around the CPU), causing those high temperatures, so mounting a CPU cooler with airflow parallel to the motherboard (which is how work almost all aftermarket coolers) helped not just the CPU temp but the NB chipset temp too.

[Vinster]

on my build I used a Cooler Master Hyper 212 Evo... kept CPU at amazing temps (45-55 C Loaded) but not my case for a hot NB

Vin