This is perfectly normal.CPU voltages and frequency are dropped when idle to decrease power consumption.In bios the power saving features are not functional ,hence it shows higher voltage and consequently higher cpu temps.
it is normal
it is to save power when system is idle
you can use high performance power plan in power plan in control panel to stop it from idling
calculate your power supply need here
my question is; my power supply brand is HEC it has got the 80 plus sign on it but it is made in china...........I was looking for a way (via software) to confirm that the power supply is giving what it ought to be giving...........I am kinda skeptic since its a lesser known brand and its made in china even thought the company is from taiwan