Active vs. Passive NB Test

[jhurst]

I wanted to test the effectiveness of active NB cooling opposed to passive. Wanted to know if there were any benefits of having a noisy NB fan. Tested with 30 minutes P95 TT:

Testing with: 2.8C on IC7

w/ Fan (5800-6000 RPM) :
NB: 37C
CPU: 49C

w/o Fan (0 RPM):
NB: 37C
CPU: 49C

Thought I would test it OC'ing.......2.8 @ 3.5ghz

w/ Fan:
NB: 40C
CPU: 53C

w/o Fan:
NB: 40C
CPU: 53C

Conclusion: NB Fan = worthless

 

[masked1]

Thanks for the info

 

[Spikey217]

Which NB fan did you use? Which passive sink did you use?

I think there would be a difference when going from a cheap sink to something like the Swiftech MCX-159.

How did you take your temp readings?

 

[mrwxyz]

i would think there would be maybe atleast 1 degree difference...

 

[jhurst]

I just used my stock Abit IC7 NB fan. And then turned it off (to simulate just a heatsink). Got my readings from MBM5. I just wanted to confirm that NB fans are just there for aesthetical purposes.

 

[Dman877]

My NF7 has been running just fine for 2 years with the northbridge fan unplugged. It was a noisy ah heck.

 

[eelw]

How did you measure the NB temp? Are you using a thermal sensor cable attached to the NB headsink or are you getting the reading from the termistor built on the Mobo? If it's the mobo's temp probe, then off course you're not going to see a difference when the NB fan is disabled.

 

[jhurst]

Why wouldn't you....you would see a difference if you unplugged the CPU fan.

 

[eelw]

Originally posted by: jhurst
Why wouldn't you....you would see a difference if you unplugged the CPU fan.

It depends on how far the mobo temp probe is from the NB. In my Shuttle XPC, the mobo probe is like 1" away from the CPU and over 8" away from the NB. So obviously the system temp is more dependent on CPU heat over NB heat.

Since the mobo on my Shuttle doesn't have a temp header where I can add a thermal sensor cable, I can't test the temperature effects of disabling the NB fan. I'm assuming your ABit board has this option. So could you try attaching a thermal sensor cable directly on the NB heatsink and then rerun your tests. This will give far more reliable results.

 

[Anubis]

just so you know i just got a Shuttle AN35N Nforce 2 400 ultra board and there is NO fan on the NB

 

[jhurst]

I would prefer passive cooling anubis....be glad there is no fan

 

[Anubis]

Originally posted by: jhurst
I would prefer passive cooling anubis....be glad there is no fan

i really dont care my Epox 8KHA+ had a fan on it and this one does not, kinda odd seeing as its a newer faster mobo, anyway even if it did have a fan the sound from my vantec tornado and 4 80mm case fans woudl drown it out

 

[RussianSensation]

Well i have 2.6@3.2 and my NB fan finally started to make noise on the IS7 about 3 months ago. It was unbearable so I turned it off completely. The system has been running stable every since even without the fan and I run SETI@HOME 24/7 so I dont see how it could get any hotter than this. So as your findings show, it is useless. How did you measure the temperature though?