there is little we can say that would be relevant.
We don't know anything about this computer or its specifications, nor about what you mean by 'trimming down'. Also, different users have different preferences. Are you a heavy gamer? Or are you into Video Editing? Do you need more RAM, or hard disk storage?
Grif Thomas has produced an extensive guide in his A few tips for Computer Newbies in the Computer Newbie forum, and others have contributed. While you may not be a Computer Newbie, the advice held there is still very relevant for all of us.
Just a note about that thread. You may need to refresh your browser a few times before the thread displays. It is archived, and it has to be retrieved from the archive servers.
I hope that helps, but if you have specific questions, please feel free to ask.
Mark
I've been out of the computer world for about 2-3years now. I just build myself a gaming computer and threw windows XP on it, then started updating. I'm current with all the updates and I want to start trimming down my OS to pull a little bit more speed out of my rig.
Thanks,
Eddy

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