Comment Three steps folks...no decay. (Score 1) 577
1) CCleaner - it just works, clean the reg too....seriously its the only reg cleaner I use.
2) Autoruns - Dragons here! so really only tweak things on the login tab unless you uber l33t
3) Defrag - optional on your 1TB drive with 970GB free
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Close contenders: add/remove progs, msconfig, PC optimser pro....yeah right