internet is flaky with XP

Hi,

I have a client running windows xp and for some reason he can’t access the internet. Every time I come over and do a release and renew ip then it will work for about 5 minutes or so then it goes down again. He is able to browse the internal network just fine but the internet is on and off. I’ve tried assigning a static ip but that seems to be flaky too. I’ve checked all network settings and everything is right. Everyone else don’t seem to have this problem, everyone else is also not using xp, they are on 2000 pro. Has anybody experience similar problem with xp?