This is REALLY annoying me. I can't listen to MP3s because the sound stutters, sometimes several times a minute, for about 1 second at a time... and it wrecks the whole song. It's not just the sound that stutters - the whole computer freezes - but as you can imagine the sound is the most obvious thing that is affected during the freeze. Also the mouse cursor is unmoveable and the CPU usage goes to 100% (and the tone of the fan changes very slightly, as it always does when its on 100% usage). I expect that many people out there have had the same symptoms sometime or other. If so they will know how frustrating it is! This problem has been happening since I upgraded my computer to a pentium 4 1.7ghz with 256mb RDRAM (and installed Windows XP at the same time). I posted a similar message 2 weeks ago and got some replies, all suggesting it was a hardware issue, and that I should open the computer to make sure the CPU is rested firmly onto the thermal tape etc. etc. I did this, but the problem remains. However I made a interesting discovery last week - the problem ONLY occurs when the LAN, or cable modem, is being used. For example someone joins on ICQ - this might trigger off a 1 second freeze/stutter. When I'm downloading/uploading its the worst - maybe several 1sec freeze/stutters in a minute. I tried temporarily disabling the ethernet and guess what - NO freezes at all. I tried reinstalling the latest XP drivers for my network card, which XP detects as "Winbond W89C940-Based Ethernet Adapter (Generic)". Still no luck. I haven't changed the ethernet card for years. I never used to have the problem when I was running Windows 98, nor when I was running Windows ME. At this time I was using a P II 350 MMX. But I know the problem is something to do with the network card. Has anyone else experienced similar problems/symptoms, or know how to fix it? I'm 99% sure its related to Windows XP and my network card. Any ideas of how I could fix it or troubleshoot the problem? Thanks!! Matt.