NB core voltage

new2spcr · Post by **new2spcr** » Tue May 12, 2009 1:15 am

Hello all,

I own (unfortunately) an Asus P5N-E SLI mobo, and apart from few bits of positive stuff like good cpu vcore undervolting feature, I'm not very happy with the NB and SB chipset can reach extremely high temperatures.
My version came with a naked SB chip and also naked mosfets in spite of
the mobo came equipped with heatsink holes to cool the components. I had to install a third party SB heatsink and I'm considering to put some leftover GPU-ram HS on the mosfets.

Most of the time, the NB heatsink is warm but not extremely hot to touch when my CPU fan (a modded Artic Cooling Alpine Pro with a Nexus 92mm fan) spins at ~1200 rpm, but if I go lower than that, say, 1000 or 900 rpm, the NB heatsink gets too hot - I can't keep my finger on it for any longer than couple of seconds.

What I'm curious about is, if I lower the NB core voltage (default setting is Auto by the way), will the crazy temperatures also go down? Put in another way; Lowering the NB core voltage, will it follow the same principle as with lowering the CPU voltage where very little performance is lost but temps can be lowered considerably?
And if it can be undervolted, must I pay attention to the memory voltage as well?

My system: Dual 2 Core at stock speed 2.00 ghz (stock voltage- 1.35, undervolted to 1.00), FSB 800 mhz, 2 gigs of RAM.

I've disabled lots of stuff that I don't use like RAID, sata controllers (those I don't use) etc, to optimize "the greener computing system" and to force the mobo to draw less watts and to perhaps cool the SB but there seems to be a limit what I can do with the NB...

Thanks.

angelkiller · Post by **angelkiller** » Wed May 13, 2009 5:37 am

Generally, I've found that stock heatsinks on NB's do the job fairly well. Not to say that they run cool, just that NB chips generally have pretty high thermal tolerances.

But I understand your desire to have a cooler running system. Undervolting the NB is probably a good idea. Since your CPU is at stock speed, there's no need for excessive voltage on the NB. There are no adverse effects from lowering the NB voltage except for system instability. So you're safe to experiment. If your system crashes unexpectedly, the voltage you have chosen is too low. So I'd definately undervolt and see how that affects the temps. I wouldn't worry about the memory. Most memory (DDR2) is spec'ed to run at 1.8v, sometimes a bit more. Memory generally runs pretty cool, so I wouldn't worry about undervolting that.

Hope this helps.

new2spcr · Post by **new2spcr** » Wed May 13, 2009 9:25 am

angelkiller wrote:Generally, I've found that stock heatsinks on NB's do the job fairly well. Not to say that they run cool, just that NB chips generally have pretty high thermal tolerances.

But I understand your desire to have a cooler running system. Undervolting the NB is probably a good idea. Since your CPU is at stock speed, there's no need for excessive voltage on the NB. There are no adverse effects from lowering the NB voltage except for system instability. So you're safe to experiment. If your system crashes unexpectedly, the voltage you have chosen is too low. So I'd definately undervolt and see how that affects the temps. I wouldn't worry about the memory. Most memory (DDR2) is spec'ed to run at 1.8v, sometimes a bit more. Memory generally runs pretty cool, so I wouldn't worry about undervolting that.

Hope this helps.

Hi Angelkiller, thanks for reply. I will give it a shot and see if temps are improved without losing stability.