Auslogics Disk Defrag.

Hard disks are by far the slowest component in your computer. CPU and memory work much faster than hard disks because they do not have moving parts. Therefore fragmented disks often become a bottleneck of the system performance.
Besides causing slowdowns, fragmentation makes the disk drive heads move too much when reading files which leads to freeze-ups and system crashes. It is important to keep your disks defragmented and optimized as much as possible.
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