I hope I did not mess up but last night when I ordered a new Western Digital Caviar Black WD6402AAEX 640GB 7200 RPM 64MB Cache SATA 6.0Gb/s 3.5" Internal Hard Drive. I know that I won't benefit from the 6.0Gb/s but the larger cache (64MB) thought might be good. My motherboard is ASUS M4A785TD-M EVO and I hope that this new drive will be compatible and I can just plug it in with out extra hardware. I can still cancel the order if it won't work. Please let me know your advice, it is my 1st build and I nervous as hell. Thank You.