TweakUI can be dangerous....I recall a friend of mine at a Computer Service center telling me that some of the big things that bring frizzle computers to him is...
1) Cable guy installs Network card...with computer "on", well, in sleep mode. Zzzap! You'd a thought the CPU fan woulda been a clue?
2) TweakUI. Delete this, that, oh and this too...reboot. Hmm, why won't it boot...uh oh.
3) Folks installing their own RAM and not grounding themselves. Apparently these folks wear their wool slippers, drag them along the carpet, pet the cat, then grab the ram and stick it in the computer. Oh to have a multitester for such occasions
(msconfig at the RUN prompt is the best way to go)
Also, this Cacheman program seems to work really well too. Its at
http://www.outertech.com/