Which fan affects GPU

[Nighthawk00]

Hey,


I've had some sensor problems with my iMac and I have written a small python script to keep the fans from running at full speed. Of course I want to make sure that the fans aren't running too slow!

I have a 2009 27" iMac (bought it just when they came out). These iMacs have 3 fans: ODD fan, CPU fan and HDD fan.

I was wondering which one of these 3 affects the GPU? I have tried to google this question and I also tried to find where the GPU is located alas with no result. Hopefully someone can give me the correct answer.


Thank you.

 

[macdudesir]

The ODD fan I do believe. For two reasons I say this, people here on macrumors told me and the gpu is right under the odd...and I have seen that fan speed up when playing a game hope I helped!

 

[Detrius]

No, it's the CPU fan. The GPU *is* right next to the optical drive, but its heat sink runs off to the left, and it's attached to the CPU heatsink, with the same fan blowing through both.

 

[Spike88]

Yes. ODD (Optical Disk Drive) cools the GPU as well.

For more info about custom fan settings, surf:

http://www.judyhan.com/otherwise/?p=1639

.

 

[SDub90]

I'm pretty sure the closest fan to the GPU is the HDD fan, but the closest fan to its heat sink is the ODD fan. I believe the ODD fan is the fan you want to look at.

 

[Detrius]

I double-checked. On that specific model, it is the optical drive fan; the heatsink goes off to the right. On most iMacs, though, it's the CPU fan.

 

[macdudesir]

in this picture, you can see the ODD fan (bottom right) and the ODD (middle right) and then the GPU heat sink right above the ODD (top right)...the ODD fan is the closest to the GPU...correct me if I'm wrong please

Picture credit goes to www.ifixit.com

 

[Nighthawk00]

So it's the ODD for sure?

 

[Detrius]

On the late 2009 27" iMac, yes it's the ODD Fan for sure.

 

[macdudesir]

So it's the ODD for sure?

Yes it is.

 

[Nighthawk00]

Thank you all very much for the quick and friendly answers.