I've always used the default AHCI driver for my SSds and Bench marks have been close to Specs and reviews. However my latest SSD (Gskill Pheonix pro was low on Sequencial and 512 K reads (Right on for 4 K random). It appears the Intel AHCI driver (Included in the Intel Matrix storage driver (Ver 9) is need for optimum performance.
Quote From Manuf comments - GSkill Pheonix Pro, Newegg comments.
Also, the AHCI driver should be the latest Intel Matrix Storage Technology driver or Rapid Storage Technology for optimum performance.
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