GPU 8800GTX Clocks

Hmm so i was exploring the settings and there is a difference in reads for the clocks. GPUZ sensor tells me while doing no 3d intensive apps like word its 300/380 and then when i game its 500/800. But when i look at Rivatuner its telling me that my core clock is 383, shader clock is 767 and memory clock 301. And the highest settings that it will let me raise to is 455 memory clock 575 gpu clock and 1175 shader clock. When the stock should be 500 GPU 800 memory and 1250 shader so i am a bit confused. Also getting diff temp reads. Speedfan is telling me 49, Riva 63, and HWMonitor 58. So im guessing that speedfan is totally off?

 

EDIT: I was looking at the wrong section in Rivatuner. Core Speeds are what they should be when gaming