I just ran
$ dd if=/dev/zero of=./largefile bs=1M count=1024
and got "1073741824 bytes (1.1 GB) copied, 10.2641 s, 105 MB/s"
read speeds are only 20 MB/s faster.
I ran the dsmeg grep thing and my laptop def. is sata 6gb/s And my bios has AHCI on. So I don't know what it could be. Anyone else have this drive? Can you test your speeds? This thing is supposed to be rated for 500 MB/s read and write!
(edited to main question)