I've had this issue on this computer for a long time. Specs Hardware eMachines T2899, upgraded with 2GB of RAM and a second harddrive. CPU-Z report Software Windows XP, SP3, automatic updates on and applied. Processes list Problem Programs lock up every few seconds or so. The time until they lock up, the time they lock up for, and what exactly happens during that moment varies. Here's a video (MPEG-4, 533KB) of the system time dialog box in windows as an example. Notice that it locks up every few seconds. Example scenarios Notepad If I hold down a key and watch the growing line very carefully, there's a very slight hiccup every few seconds. Subspace/Continuum In this 2D sprite-based little MMO from the 90's, during a "freeze" the game's framerate simply goes down to about 1-5 for a few seconds. Firefox Sometimes when I'm clicking and dragging tabs to rearrange them, the system will think I held my click longer than I actually did (because it'll freeze at that moment), and it ends up thinking I dragged a tab out of the tab bar (thus launching it in a new window). Quake 2 In this 90's 3D game, whenever a "freeze" happens the game keeps going graphically, but does not respond to any input (meaning for that second or two it keeps me moving in the direction I was headed in). Runescape In this modern MMO, whenever a "freeze" happens the game is unresponsive (and does not upgrade graphically at all) for up to a few seconds. Doesn't happen here... Mouse movement. Audio (haven't tried an unbuffered source, suggestions on one?) Anywhere in Linux (even runescape runs without a hiccup). Troubleshooting steps and results. Check the task manager? No discernible CPU usage or differences during a "freeze". Safe mode? Happens in safe mode as well. Switch AVs? Changed from Avast to MSE, no fix. LOL FORMAT??? This happened on my old installation of windows on this machine as well, and this installation was done with a clean XP install disc. Check the performance monitor for any values that peak during a freeze? I've narrowed down a few things that spike at a freeze, but don't know what to make of it. -Cache- Sync Data Maps/Sec (hits 100%) -Memory- Page Faults/Sec (hits 100%) Transition Faults/Sec (hits 100%) -PhysicalDisk- Avg. Disk Bytes/Write (hits 100%) Disk Writes/Sec (goes from 0% to 8-12%) Disable write caching? Disabled it on both drives and restarted, still have the issue.