Hi there! I´m using th i3 3220 IGP. In its data sheet it says that its base frecuency is 650 Mhz, i performed an OC to 1200 Mhz, and when its idle, the SAndra 2012, PC Wizard, Aida 64, all of them says that its working at 350 Mhz. I suppose it should be at 650 Mhz, i´m just curious, ´cause when i need te full speed it goes to 1200 Mhz. Is that OK? Thanks!
That's normal, its frequency will increase when its needed, just like Turbo mode for the CPU cores.
My 3570K's HD 4000 runs at 350 MHz on the windows desktop too. If you want to see the increase, just run GPU-Z in the background while playing a game or the render test in GPU-Z itself. It immediately jumps to 1150 MHz.