Solution to coil whine
Posted: Mon Oct 06, 2008 8:26 am
I recently built a system with a GeForce 9600GT and was a bit disappointed to hear the strange noises coming from the PC. I've googled my head off trying to find out what's happening here, and that's how I found these forums...
Anyway I worked out the noise was actually coming from the PSU, not the graphics card, even though it only happens during graphical operations (including such trivial things as selecting menu options would make it click), and didn't happen at all before I installed the GLX drivers. The PSU, for information, is an Antec Earthwatts 380W
What seems to be happening here is that the PWM signal from the voltage regulators on the graphics card are getting back up to the power supply, and shaking that big old inductor all over the place. Not wanting to open up a brand new PSU, I thought, there must be a better way to solve this problem.
So... I put a 4700uF capacitor across the 12V rail, wired into a PCIe power extension lead. It doesn't completely eliminate the noise, but it certainly reduces it. I guess more capacitance is required. I should maybe make some sound recordings with and without it.
Oh and of course I take no responsibility for any damage you do to your computer by trying this out! I can't imagine what harm it could possibly do, but you never know.
Anyway I worked out the noise was actually coming from the PSU, not the graphics card, even though it only happens during graphical operations (including such trivial things as selecting menu options would make it click), and didn't happen at all before I installed the GLX drivers. The PSU, for information, is an Antec Earthwatts 380W
What seems to be happening here is that the PWM signal from the voltage regulators on the graphics card are getting back up to the power supply, and shaking that big old inductor all over the place. Not wanting to open up a brand new PSU, I thought, there must be a better way to solve this problem.
So... I put a 4700uF capacitor across the 12V rail, wired into a PCIe power extension lead. It doesn't completely eliminate the noise, but it certainly reduces it. I guess more capacitance is required. I should maybe make some sound recordings with and without it.
Oh and of course I take no responsibility for any damage you do to your computer by trying this out! I can't imagine what harm it could possibly do, but you never know.