cpu usage tool? 100% usage with no apparent reason

[Truebrit]

Is there a tool that shows how much cpu power a certain app is using in real time, like the task manager does for memory usage? The reason i ask is i've started to get the dreaded 100% usage with no apparent reason. I havn't seen that problem for years.

I have tried the latest beta drivers, defragged and checked my HD for errors, any idea what could be causing it?

Intel® Core™2 Quad Extreme QX9650 Processor (3.0GHz, 12MB Cache, 1333MHz)

Vista Ultimate Edition 64 bit main O/S

Coolermaster Cosmos S Ultra Performance Aluminium Chassis with 1250W PSU

PCI-Express Mainboard - SLi nForce 780i SLi - Intel Core2Duo/Quad Core - ATX

8GB DDR2 800MHz Memory (4 x 2GB)

Nvidia GTX260

Creative Labs Sound Blaster X-Fi Xtreme Gamer Sound Card

 

[Truebrit]

In the cpu column, is that a percentage value? I looked at those numbers earlier when my cpu read 100% and my game lagged, but they were mostly 00 or 01. Right now my cpu usage is 2% and they're all at 00 apart from system idle which is at 99.

Task manager shows which software is using the cpu and how much. Open the processes tab and left click the 'CPU' column header (to list programs in order of cpu usage).