Detecting Sources of Sporadic CPU Spikes

I watch TV (live or recorded) in Media Center and browse the internet... This combination occassionally spikes CPU usage to 100% on my AMD64 X2 5000+ (Dual core 2.6 ghz)

This has been an issue with both 32 bit and since upgrading to 64 bit. The issue causes my video to stutter or freeze. I know the CPU spikes at these time because I see it on my desktop gadget

I do run Carbonite in the background... but nothing else I can think of other than what comes with the OS

It seems like any time I run Task Manager to detect the issue the problem doesn't arise (there must be some corollary to Murphy's law for this).

Is there a tool to report on CPU hogs when CPU utilization spikes? Any other diagnostic methods to consider?

Check your Latency. Maybe there is a driver problem and too many deferred procedure calls.

Thanks!

I have discovered that latency spikes at times.

I am in the process of downloading a couple of "Optional" driver updates through Windows Update to see if it helps. If not, I will try to determine the source of the latency.

I will continue to dig in, but I beleive the new drivers have helped quite a bit.

Instead of 5-10 seconds of stutter, I am now just experiencing a second or two, and it also seems less frequent. I updated the Network drivers, and also went out and got the latest ATI drivers for my video card.

The latencies still being reported are shorter in duration and also not as high.

I will selectively disable components and find out which drivers are the potential culprits.

Looks like you are on the right track. You may want to run Process Explorer. Let it run for a while and then check the performance graph (in Properties) of the DPC process ( if you prioritize by processes, it should be the second one on top).