500mb limit on Vertex 3 120gb raid0?

Hi fellow tom's. I recently purchased my second Vertex 3 120gb ssd for a raid 0 set up. i got my raid 0 setup working properly as a boot drive with the 128strip. when im bench marking the raid on as ssd and atto. im only getting about 500-560read and 200-250 write speed. ive seen people get a benchmark of about 900-1gb read and 500+ write and i also updated my bios to 1502, latest bios for the crosshair and dled the latest raid drivers also. so im not sure whats bottle necking my raid? any information or solution from people with similar problems would be appreciated. Thanks in advance
heres my system specs
Amd-fx 8120 cpu
asus crosshair v mb
16gb corsair vengeance 1333mhz rams
2x 120gb vertex 3 ssd raid0
http://imageshack.us/f/198/raidr.jpg/ here is a pic of my bench marks