system
10
I agree with RejZoR.
In safe mode, Windows only uses PIO mode transfer.
Since defraggers uses sector based defragmentation, avast! does not scan any files that are being defragmented.
Unless you don’t have enough RAM to run your defragger, you shouldn’t have to turn off avast! in order to defrag your HDD. (You should upgrade your memory if that’s the case :))