Sony MX - Manual (Page 56)

Configuring Your VAIO Computer
Hard Disk Drive Partition
To maintain optimum system performance, you should defragment your computer's D partition regularly.
To improve the performance of Sony audio and video software applications, the hard disk drive on your computer has been
formatted with two partitions, C and D. Some Sony software applications save files to the D partition. This prevents large
video captures from consuming the available space on your C partition.
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