Windows 7 Keeps Throttling Processor To 25%

My power settings do not tell Windows 7 to cap processor performance at 25%. I've got a Dell XPS M1330, which is a fairly "old" machine in the modern market, but still performs well when Windows 7 isn't pulling this crap. I've tried resetting power settings, I've brought it in to a shop to check the CPU fan and core temperature and that all checked out, but the Resource Monitor still shows the processor being throttled to a quarter of it's potential.