Typically, when I've not got Steam window opened (As in, not looking at it) my Xfx 5870 Core clock's at 157Mhz according to MSI when doing light browsing etc. However as soon as I open Steam to view the Store, Community etc. my 5870 instantly clocks to max load (850Mhz) which then forces the temperatures up by an average of 10degrees. I wouldn't call this an alarming thing but the fan then increases its speed to combat the increase in temperatures, so my card makes noise just because it's viewing on Steam. Anyway to stop my card doing this?