Windows 7: DPC's Queued/Sec Off the charts!! in performance monitor

My computer has been acting slow and on occasion shut itself down for no particular reason, playing PC games used to be easy, now if I try to play Halo 1, it will shut off because the fan is on hyper overdrive!! So I decided to check out the performance monitor. And a lot of things seem to go off the chart, such as DPC's Queued/Sec, and %idle time, %DPC time, %C1 time...but the 2 that are WAY up there are DPC's Queued/Sec, and C1 Transitions/Sec...but anyways I think this might be the reason why my computer is Sh*t now, pardon my language. Please Help.