Slightly Mysterious CPU Fan Issue

[uncle_rufus]

Hey all,

I'm not entirely new to the forum, as I had an account a while back when I bought my PC from OcUK, but it's been long deactivated now so I had to make a new one. I'm having some issues lately which I can't seem to get to the bottom of, so I hope someone can help. (SHORT VERSION AT BOTTOM!!!)

My PC was an OcUK "Ultima" bundle from a fair few years ago now... Spec was roughly:

Abit IP35V mobo
Intel Q6600 GO Stepping 2.4 Ghz
2Gb Corsair XMS2 DDR2 800Mhz
Nvidia 8800 GTS 512Mb
etc. and in an Antec 900

A little while after buying it, I picked up 4Gb of 800Mhz XMS2 around the time DDR2 was mega cheap and switched it in (removed the existing 2Gb). From then until a month ago the PC has been running just fine, think I must have bought at a good time as it still ran fairly nicely.

While I wait to see what happens before putting together a new PC, I thought I'd try to inject a bit of life into the current one by replacing the graphics card and doing a clean install to Win7 64-bit (from XP 32). So I picked up an MSI GTX560 Ti and went ahead with it.

It went fine, clean install has made the system slightly snappier and more responsive, but there's one thing I can't seem to work out. Since upgrading the card (both before and after I installed Win 7) there has been significant fan noise ramping up whenever I play any games etc.

At first I naturally suspected the new graphics card, but both MSI's "Afterburner" app and SpeedFan show the temperature of the 560 never goes much above about 55 degrees even under heavy Kombustor/Furmark tests, and Afterburner reports the fan speed as staying at it's minimum (40%/1740 rpm).

I don't think any of my case fans are connected via 3-pin, so that ruled those out. So from what I can tell it's the CPU fan, but strangely CoreTemp/Speedfan both report all 4 cores don't get particularly hot, maybe around 50 - 60 degrees under most tasks, but still the fan speed goes right up fairly quickly. I also don't seem to be able to use Speedfan to stop it happening, unless I haven't configured it properly.

That's the info that springs to mind, please let me know if any more info is needed and I hope someone can help!

SHORT VERSION:
Got new GTX560 Ti in Q6600 system, which has caused CPU fan to go to very high speed during games. Fairly sure it's the CPU fan, but no idea why.

 

[R.C.Anderson]

I think it's unlikely to be the CPU fan, what I do when I'm unsure which fan it is, is I open the side of the case whilst the PC is running (and making excess noise) and in turn, stop individual fans by apply pressure with my finger to the centre of the fan (you don't want to stick your fingers in the fins, that'll hurt) from that, you'll know which fan it is for sure

 

[uncle_rufus]

Sounds like an idea, although it will be difficult to do that with my Arctic Freezer 7 because the middle part of the fan is behind a cover :S.

I did stumble onto something which might make sense on Abit's website. There's an additional temperature reading for "PWM" which appears as "AUX" on SpeedFan, which in my limited understanding is some sort of chip near the CPU which regulates the current from the PSU and can get quite hot (safe up to 120 degrees though apparently). Does this sound plausible?

Update: I noticed SpeedFan wouldn't actually allow me to control the fan speeds, so I had a poke around in the BIOS and found that there's an Abit automatic fan control enabled, but that it's target temp was set to 50 degrees... so I'm going to try changing that to 60 and see if it makes any difference... Failing that I guess if I disable the Abit speed control then SpeedFan might be able to work as intended.