I have recently installed a brand new ASUS gtx680 DCii Top Edition card. It runs perfectly (graphics are insane) but one of the fans is really loud at idle.
The temp is still around 24 to 28 degrees which is quite cool.
GPU tweak says that the fan is running at 20% and you cannot lower it.
My PC set up is about a year old so I was wondering if it was my PC or the card that is causing it to be so loud.
That's really unfortunate. Has it always been loud since you 1st bought it? Is it definitely just 1 fan on the GPU?
I have seen DCII TOP in action on a couple of 670's, and I wouldn't have said it was abnormally loud. Playing with the fan settings was a good test, but if it's still overly loud at the lowest setting, I think you have a problem... Also given that it's only one of the fans making the sound then something isn't right.
Does it make the sound at high setting too? Might sound dumb, but double check there is nothing obstructing that fan at all.
You could theoretically change out a fan on the cooler for a new one... but I wouldn't. Send that sucker back! I would think you have at least 3yrs warranty on that beast.
As easy as it might be to change a fan, you should get what you pay for.
Personally I would not change it for that cooler. With the Asus DCii Top Edition you've got one of the most respected and recommended AM Coolers in the business.
Lets go back a step... so it is 'both' fans.... might not be malfunctioning hardware. First thing to check...try setting the GPU back to stock speeds, frequencies and voltages if its OC'ed at all. Have you checked the fan speed profiles with a different application? Maybe your current GPU Tweak is not behaving correctly? I like MSI Afterburner. It will work with other manufacturers GPUs. Just find a different one from what you are using.
Maybe trying to adjust the fan speeds in a different app will help. You say they are always loud even at 20%. Do they get even louder as you go up? I am wondering whether they not going down the lower setting even though your current GPU Tweak says they are. If you go up past 50-60% and they sound the same, then it isn't coming down. You'll definitely notice a difference in sound.