incredible debits

After using it for 3 years a crucial ssd M4 120GB (420mo sequential read, 200 in writing) on ​​a desktop PC, I began to feel cramped.
I read a lot of comparative on the net, before I decide. I'm running for a month now, and it's frankly nice not having to constantly make room! CrystalDiskMark shows 500MB sequential write, 510 in reading. The benchmark of the Magician software even more optimistic, gives 520 in writing, 550 in reading (!).
The TLC used memory does not make me at all afraid, Samsung gives to a cycle of 150 shall succeed to ... I do not even half.
However, a note: I first connected it to a SATA 3 SSD random port on my Asus P8P67, and I found myself with catastrophic rates ... It came from the SATA port 3: all are not equal, and those of Marvell mark on my motherboard are zero. Finally, connect your SATA SSD priority to native 3 doors, not those "additional".