Most new machines have Vista installed.. If so, then you'll need to check the game site to see if they've got any Vista compatible patches.. It may be a compatibility issue.
If you're sure it's XP Media Center, then start by disabling all the background programs and services that are not needed.. Similar problems are seen with various antivirus programs and antispyware programs.. If Norton or McAfee, have you tried disabling them prior to playing the game? Disabling their firewalls temporarily to see if that's the culprit?
Confirmed with the game site that the video card and it's drivers are supported?
Updated both the video and audio drivers on the machine?
Hope this helps.
Grif
All these same games play on my dell 8250 with xp pro, my new dell has xp media, 4gig of ram qx6700 processor, nvidia sli gtx 8800 video,sb x-fi sound, I have updated everything i can. When it tries to load Fear XP, It comes up with FEARXP has encountered a problem and must close. When I try to load Quake 4, the screen just blinks and does nothing.I have downloaded all updates for both games.Dell techs tell me its not a hardware problem, but a software, could something be configured wrong?

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