Extreme lag on opening screen/menu/game

[DIGI Byte]

how many programs are running in the background?
any heavy resource things? or just a lot?

I have a game that is only lag with menu's as well, its related to my power supply which makes a high pitch squeal only a few people can hear, myself included, the game runs smoothly, but the menu's are a lag little monster
I doubt its your power supply though