Asus HD 6950 fan stuck at 4000 RPM

[just Scott]

So my friend recently built a computer using this GPU and he's been complaining about the GPU fan being too loud. He says the fan will randomly spin up to 100% for no reason and sometimes stay like that. We've tried MSI Afterburner and Asus's own fan control tool, but the manual fan control doesn't work on them.

He's just checked GPU-z and it's displaying the fan speed % correctly, but the fan RPM never changes. So changing the fan speed in Afterburner doesn't affect the noise level at all. It is stuck at 4000ish RPM, which does sound too fast. Especially when he's not running any 3D applications or anything.

Any ideas why the fan control on any software won't work? Could the cooler on the GPU be faulty?

The power supply is a Corsair TX650 and he's running Windows 7. Mobo is Gigabyte P67 UD3 B3 with an i5 2500k.

Cheers

 

[spleenharvester]

Temps?

 

[Tealc]

The PWM signal from the card isn't getting to the fan. If just the first three wires are connected the fan will run at full speed no matter what the duty cycle. It could be that the fourth wire has a break somewhere or isn't fully pushed home into the onboard fan connector. After just re-reading it's probably very close to making a contact and sometimes is connected and slows the fan while other times it shows no connection. Or it could be a faulty fan.

Here's a thought though are both fans spinning up to breakneck speed or is it just the one? Only one fan has a speed sensing wire by the look of the image below yet both have blue PWM wires. Could one fan be faulty/bad connection or both?

You might be able to see the fan connector under the shroud of the cooler.

Make sure it's pushed all the way home.

Any further wiring checks will probably inolve removing the shroud of the cooler and potentially invalidating your warranty.

 

[just Scott]

Temps?

49c idle, not sure about load.

The PWM signal from the card isn't getting to the fan. If just the first three wires are connected the fan will run at full speed no matter what the duty cycle. It could be that the fourth wire has a break somewhere or isn't fully pushed home into the onboard fan connector. After just re-reading it's probably very close to making a contact and sometimes is connected and slows the fan while other times it shows no connection. Or it could be a faulty fan.

Here's a thought though are both fans spinning up to breakneck speed or is it just the one? Only one fan has a speed sensing wire by the look of the image below yet both have blue PWM wires. Could one fan be faulty/bad connection or both?

You might be able to see the fan connector under the shroud of the cooler.

Make sure it's pushed all the way home.

Any further wiring checks will probably inolve removing the shroud of the cooler and potentially invalidating your warranty.

He's checked the wires and they all seem fine. And yeah, it's just 1 fan that's stuck with the high RPM.

 

[just Scott]

Anyone? He still hasn't fixed this.

 

[spleenharvester]

RMA job I expect, the wire will have probably come away from the fan itself.

 

[Tealc]

RMA job I expect, the wire will have probably come away from the fan itself.

^This I expect too. Not much you can do that wouldn't actually invalidate warranty anyway.