Hello, i just want to ask some question. i bought samsung ssd 840 evo 250gb. in some review, most all write speed and read all 500 MB/s higher. But in my system, my samsung ssd 840 evo only running in 403 MB/s on read and 390 MB/s on write. i've already follow the optimization ssd, i've used sata 6gb/s port, only installing chipset driver only, disable page file, disable prefetch, system restore, indexing, etc. i'm using asrock Z87 extreme 4 mobo with i7 4770k with 16 GB ram and windows 7 ultimate 64 bit sp1. any advice would be helpfull...