Millisecond Forums

Thank you! I lowered the resolution of the video and tried a number of different codecs and finally found one with which it worked (H.264(x264)).

All of the things you mention (codec, graphics driver, insufficient processing power) are potential causes. The specific symptom "slow & freezing" would point to either a remaining codec issue or insufficient performance *given* the way the AVIs are encoded. (AVI is a container format, i.e., the file extension alone says little about the actual video codec used). Trying to play back a HD-resolution video encoded with some modern codec (for which older graphics cards / drivers may not provide direct hardware support), can easily overwhelm an older system in terms of processing demands and lead to stuttering and/or apparent freezing.

I would try re-encoding the videos in question, possibly at a lower resolution and using a different codec, to see if this affects the play back performance on the system in question.