Gigabyte P35 DS3P - CPU fan control problems

[Magnets]

Ever since i overclocked my CPU, e6420 to 2.6 (1333FSB) i have had problems with the CPU fan control on my motherboard. The motherboard isn't overclocked.

When i cold boot, the CPU fan control does not work, it just runs at full speed.(even though the BIOS says it's on 'Legacy' control method)

I have to start up, then reboot. Or sometimes reboot, enter BIOS, save, exit, reboot. For it to run the fan at lower speeds.

If i enter the BIOS when the CPU fan is running at full speed, the CPU fan RPM monitor sometimes flashes between 2500 and 0.
When the fan control is working properly (after reboot) it doesn't flash.

I've tried resetting the CMOS, twice.

Also, sometimes i notice my mobo has reverted to stock speeds.
I am using 'Legacy' fan control method, and PWM, HSF is arctic freezer.

[Kumagoro]

I have mine on auto rather than selecting a specific control method.

[Magnets]

I have mine on auto rather than selecting a specific control method.

What RPM does it keep your fan at?

Mine goes from ~1000 RPM idle, to 1500RPM under load.

[acrobat]

Do you have the latest BIOS firmware from gigabyte's website?

Other than that, I don't know much about it. I just know that there are 2 settings which each have a few options so there are quite a few variations to try, so it can take a lot of trial and error to find one that works. I have the DS4 but mine is a 965p, not the new P35. But anyway, I did trial and error, and tried AUTO/PWM, AUTO/LEGACY, and LEGACY/PWM, etc.... (not sure if those are the right way round, but there was loads of options and I tried all kinds of ways basically.) I think I settled on Legacy / Auto now, although I'd have to check to be sure.

It runs the fan at about 1050RPM or so, and if the CPU ever gets really stressed, it speeded up up to full speed or close.

Anyway, one thing I wanted to mention, is that on my DS4, the CPU fan control is a bit unusual. The first time I switched my PC on after first building it, I saw it booting past the bios and stuff, and then I looked into the case and noticed the fan wasn't spinning... Just as I began to wet my pants, the fan started spinning. I thought something was wrong, but evidently, its just a bit odd like that.

After months of messing around with various settings though, my pc is running well now, but still, the fan doesn't always start immediately. Usually its about 3 or 4 seconds after starting the PC. Just thought I'd mention that too. (Its evidently normal)

[merdat]

Acrobat,

Yes your right . On the DS4 the CPU Fan has a slight delay---nothing to worry about even with a stock cooler but gives you a fright the first time it is switched on after build.

[acrobat]

sure did

p.s. I have contacted Gigabyte a few times about various things, using the support link on their website. I was amazed at how good they where. Really quick, pleasent replies with proper english. I wouldn't suggest abusing it obviouly, but its nice to know the option is there incase you ever need it.