I've read of similar problems, but none quite like this. EVERY time I OPEN a video or audio file, watch video on the web, view flash content, or use a java app on the web, the CPU use begins to climb out of control until it reaches 100%. Then the videos, audio, etc. become choppy and skip, and the computer grinds to a halt until I quit the media player or browser. It usually takes about 3 minutes for the CPU use to reach 100%.

Here is my system information:
Machine: Sony VAIO PCG-K45 15"
OS: Microsoft Windows XP Home (Version 5.1 Build 2600.xpsp_sp2_gdr.070227-2254: Service PACK 2)
Memory: 512 MB PC2100 266 MHZ SODIMM DDR RAM
Page File: 1024 MB static
Graphics: ATI Radeon IGP 345M
Audio: Realtek AC97

My Windows installation isn't off a Windows disc, but from the System Restore discs provided by Sony. I regularly use anti-virus and anti-malware scanners, and my computer is clean. My graphics and audio drivers are up-to-date. My BIOS is up-to-date. My HDD DMA settings are CORRECT. My registry is error-free.

Basically, every time I try watching video, listening to music, or playing games on the web, this problem shows itself. It first started about three weeks ago, and it has persisted through a reformat. Every video player, every audio player, every browser exhibits this problem. Aside from this problem, the computer runs beautifully. It is maddening, because I can't figure out what's wrong. What is going on?

Edit: I posted it under "hardware," because it encompasses such a wide range of software, that I'm afraid this might be a hardware issue... I'm not sure anymore.Seeing as the problem affects a CPU could you please tell us what it is. (ie Manufacturer, Model, Speed, Socket, Dual-Core? etc.)Oops, sorry. I forgot that. It's a Mobile Intel Pentium 4 Processor 538 3.20GHz; 533 MHz front side bus; 1 MB L2 cache; Socket 479; single-core.