GTX 580 Lightning Fan Speed

[Overclocked_Keyboard]

My HAF 932 case has recently been running extremely loud when doing minute tasks like surfing the web. I've narrowed it down to the fans on my GTX 580 Lightning. I'm using MSI afterburner to show temps/fan speed. Basically afterburner says the fans are going at 30% and temps are normal (Idling ~32C) but the strange thing is if I modify the fan speed from 30-60% noise level doesn't change. I then investigated further and saw the fans do not slow down below 60%. If I force 50% fan speed afterburner says 50% and the graph shows 50% but the fans are actually at 60%. If I go above 60% the fans will get faster and if I go back down to 60% or lower they will idle at 60%. It seldom slows down but I have yet to find any correlation as to why it slows down (No temp difference, no fan option changes). Seems to be an entirely random occurrence.

What could possibly be causing this?

Asus P8Z68 V-Pro is the mobo I'm using. The card is NOT overclocked and my current driver is 285.62.

 

[-RockMan-]

If your tempatures are low and steady but the fan is loud...
Please download this and the gadget for windows so you can see it without double clicking the program.
Real Temp - CPU temperature monitoring

Newegg.com - ZALMAN VF3000F(GTX580/570) EBR Bearing Dual 92mm Fans, FanMate 2, IHD Technology for Nvidia Fermi GTX580/570 VGA Cooler
If you can't bare the noise of your original fan that will do fine for you.
Since you have a 932 haf case check bios to make sure the system fan isn't at 100% along with cpu.
Lastly check your game settings and make sure the FPS is not to high, sometimes vGA cards will get noisy when they work on high end games.