I built a system AsRock P76 Extreme4 Gen3 I7-2700 overclocked to 4.7. When idling it runs 1.6. Now my wife plays Farmville on Facebook and she says it is slow. Does the fact that it idles down that far,slow her farming? Is there anyway to raise the idle speed to ,say 2.8 ?
No way to raise the idle speed, no because it's already dynamic, as it is. The High Performance power plan in Windows would do the trick, but that would make it run at a solid 4.7 all the time, effectively disabling SpeedStep (which is actually how a lot of people run their OC's anyway).
Not actually disabling SpeedStep and just using the High Performance profile gives you the advantage of being able to put it back to Balanced to let it clock back down when you don't need the extra speed.
The low speed shouldn't really even be a problem though, since SpeedStep allows the CPU to speed all the way up to your OC that you have set, when needed.