8600M GT graphics card question :)

Hi there,
I have a Dell M1530, 2.4Ghz T8300, 256mb 8600GT DDR3 graphics card.
I've overclocked it to 600/1200/800MHz (Core/Shader/Memory) in Rivatuner, although this shows up as 648/1296/799MHz in the hardware monitor I guess this is because the Memory clock brings the other two up. It hits about 80C when gaming, maximum. Now, I have the problem of my card underclocking itself when under load - is there a way I can stop this?

It's frustrating because the card isn't getting very hot (the danger zone is about 100C+ according to Nvidia) and I feel like I could get a bit more juice out of it without overheating it.

Now I know that the card has issues with breaking under stress, but I have a warranty and because of this known problem, Dell don't think twice about replacing it when it goes wrong. So if it does break, no real problem. I've undervolted my CPU too so the temperatures are reduced here.

Also, if I can't get rid of this auto-underclock, could I increase one of the 3 settings without it underclocking itself? (I.e. does one of the settings not increase the heat of the card?)

Thanks in advance for your help!

 

What's showing it as the second set of clocks? Run GPU-Z and use that for determining your actual clock speeds after setting it in Rivatuner. It the core really is 648, that's very high and could be the source of your downclocking.

 

Odd. I used GPU-Z and it doesn't agree with the Rivatuner hardware monitor at all. GPU-Z shows the clocks as I set them (I.e. 600/1200/800).