Help needed: Crucial M550 256GB mSATA low speeds

Dear forumites,

I just bought and installed a Crucial M550 256GB mSATA drive onto an ASRock FM2A88X-ITX+ motherboard.

Fresh Windows 7 Home Premium install, partitioned the drive and ran a couple of benchmark tests as usual. The CrystalDiskMark results you can see below reveal that the drive seems to be limited to SATA 2(?) speeds whilst the ASRock product page clearly states that its mSATA connector supports 6Gb/s.

I'm not very experienced when it comes to SSD/HDD issues since I haven't gotten any up until now. If anybody could help me fix this, I'd greatly appreciate it.

Kind regards,


-cerberus-, Belgium


Results

Are you using sata or msata? What motherboard are you using?

As stated in the original post: an ASRock FM2A88X-ITX+ motherboard, and I'm using the motherboard's mSATA connector.

Is it running in AHCI mode? Or does that not apply anymore to mSata?

Just had a wee look at the storage settings in the BIOS; SATA mode is set to AHCI. I assume this covers mSATA as well...

On a side note, I got a reply from Crucial support advising me to let the drive idle from 6 to 8 hours to do some "Active Garbage Collection" because "The behavior you are describing is consistent with deleted cells not being cleaned from your drive." The rest of the email is pretty much a word for word copypaste from this particular topic on the Crucial boards. How all of this is relevant to my problem, I have no clue since this is a brand new drive but alright, I'll give it a shot regardless.

Anybody, please? This drive issue is really grinding my gears and Crucial's support hasn't solved a thing.