Ultra DMA (UDMA) Modes

[ultim]

Hi,

Just looking at output of my drive from HD Tune

Firmware version : 1AA01113
Serial number : xxx
Buffer size : 33553920 bytes
Standard : ATA/ATAPI-0 - SATA II
Supported mode : UDMA Mode 7 (Ultra ATA/512)
Current mode : UDMA Mode 5 (Ultra ATA/100)

Current UDMA mode is 5. How do i change it to 7? I assume changing to 7 will make my drive faster.