After weeks of trying to sort out major stutters during gameplay despite high fps
I have finally solved the issue. On going into task manager I noticed that windows media player networking service was sometimes using 80% of the CPU.
I've tried all the tweaks to no effect but after disabling this service I have now just played for two hours with no problems.
I hope this helps someone else because it was certainly driving me mad and I was thinking of reinstalling XP!
Here's a link about this issue
http://social.answers.microsoft.com/Forums/en-US/w7music/thread/9abc9abb-4c39-4e90-ae75-2f1cb02d5843
