New SSD, Read/Write speed low.

I got my new SSD today, i set everything right in bios, AHCI enabled on my Marvell Controller that supports 6gb/s.



Samsung Magician says it's all fine, that i'm connected to SATA3 6Gb/s.



I'm not sure whats wrong.



Sequential Read = 383mb/s and write 189mb/s.

New SSD, Read/Write speed low.