If you're having stutter problems playing 1280x720 mp4 (H264) videos on your Acer Aspire One netbook, you may want to try the following out. My netbook specs: Acer Aspire One D250 1.66 GHz Atom CPU (no overclocking) 1GB DDR-2 RAM @ 533MHz single-channel Intel GMA950 graphics Windows XP SP3 Here's what happened: I couldn't get my 1280x720 .mp4 files to play without serious stutter problems in VLC media player (ver 1.1.5). I downloaded and installed K-Lite codec pack (K-Lite_Codec_Pack_700_Full.exe) and managed to see [b]significant[/b] improvement when playing 1280x720 .mp4 videos (in Windows Media Player 11), but there were some videos that lagged :( . Mind if you try installing the K-Lite codec pack and report the results here?