Temp sensors in computer.

[skim36]

Ok,  I built a new computer and I'm new to the fan controllers that are out there.  I placed the cpu sensor just under the heatsink and great, the temps are within 1 degree of what the bios says.  Now my GPU is a different story.  nvidia monitor says it's idling at 44c, but wherever I put that sensor, I can't get close to that.  Slid it in by the core, all around the heatsink, taped to the back where the core should be.  I can get within 8 degrees...that's all.  Worth noting it's going on a galaxy 8800GT with the aftermarket zalman type cooler.  Any modders out there can help?  I really would hate to pull the heatsink off, and I've googled this thing to death.  Any input would be appreciated.  Thanks

[DaOld Man]

Why is an 8 degree difference so important?

[ahofle]

And is there some reason you don't trust the CPU and GPU sensors in the first place?