Gpu weirdness :)

[Milz42]

I am running a number of stres tests to make sure my system is 100% stable (also so the computer runs nice and cool when idle) when i run prime95 and Msi kombustor i notice that my GPU goes from 99% load to 50-70% load when prime 95 is active? is there any reason for this? when prime 95 isnt running my gpu runs at 99% when stress tested in kombustor.

Weird or what! lol

Thanks for any advice.
Dave.

My cpu is i53750k @4ghz
gpu Sapphire 7850 oc (twin fan)
Psu Coolmaster GX750W