So there's a possibility that I'm posting in the wrong section but I'm 90% sure this is a graphics card problem. I'm using a dell studio 17, running windows 7 with an i7 processor and 6GB RAM with a ATI Mobility Radeon HD 4650 graphics card. The problem is that after viewing a 1080p clip that is about 5 minutes long in VLC Media Player, things go very wrong. Sometimes the whole monitor goes black and the audio lags or just comes to a complete halt. Other times the video plays out but is very laggy with out of sync audio. After closing VLC the lag persists. Task manager tells me that the CPU is only running at 5%; there aren't a lot of programs running simultaneously and yet anything I do will present itself in a jumpy fashion i.e. if I open a program, it will open promptly but with stutter across the screen as it enlarges itself. I definitely have the latest driver software and restarting seems to solve the problem but I really want to be able to watch HD videos without this problem. Thanks in advance for your time. EDIT: Tried watching the video again and it seemed to work ok except that I noticed by the end of it my pointer was massive. At least 5 times as big as normal. Rebooting/Hibernating/Sleep fixes this. EDIT: Tried using windows media player and it worked! (Apart from the big pointer which still occurred) What I don't understand is why my computer continues to lag after I've closed VLC. Any questions? Comments?