Updated drivers - GPU drops 10C

So, just updated to the 185.20 drivers for my 9500M GS (G1Sn). My max GPU temps as recorded by rivatuner have gone down 10C. They were ~95C while gaming on previous drivers, now they are ~85C no matter how long I play. Clocks are the same and I think 3dmark05 score stayed the same(ish), too.

Without OC(2ghz 475/400) and 179.48 drivers I got 7287 - temps ~95.
With OC(2,1ghz 530/430) and 185.20 drivers 7976, sounds about right? Only thing that with these, temps are ~85.

What are the options and is it likely that a driver would have messed up the temperature readings before? Or is this driver somehow not using all performance and the card isn't getting as hot ? Im not sure, but fps might've gone down some.
This new driver is a bit different than others (new graphic options, more advanced control panel).

e: Oh, btw idle temp is the same still. What is going on ?

 

idle temp stays the same because the fans only kick in after the gpu gets to a certain temp, say 60, which stays the same regardless of the drivers since it's written into the bios.

 

Yeah, I was thinking these new drivers would've read the temperature sensor differently - whether it's incorrectly(real temp 95) or correctly(real temp 85) - but as idle temp is the same, that isn't the case ?

 

Do you download new drivers from nVidia website or ASUS website?

 

laptopvideo2go - but it seems its back to normal now, don't know what that was about.

 

It is not necessary that the reading error is simply a static offset; it can be a error that linearly (or nonlinearly) increases with the value of the temperature.

Or maybe the drivers are highly optimized -- although I doubt such a high temperature drop would be obtained simply by optimizations. Erroneous reading or clock changes are more likely, I think. But I'm just guessing

 

Forceware downclocks GPUs when they are not in use, so the idle wouldn't change.

 

Unless errors were added (or removed) to the sensor reading, which was the assumption under discussion