Partial BS. Tom's has run articles comparing defraged and non defraged drives. They and all other research show little differences with today's current OS's. The same is true of registry cleaning. In fact when Tom's ran a comparison of speed up software (all of them defraged, reg. cleaned and did a disk clean up) there was no appreciable improvement. Back tot he registry; there is a greater chance these tools will cause problems than fix or improve the system. So why does Tom's run the crap when their own testing shows it is useless. Oh ya to get paid by the vendors. LET THE READER BEWARE!