Sorry should also say I'm on the A02 bios running uefi and gpt partition so Magician software won't tune ssd!

The mITX mobo on the x51 runs the intel H61 chipset.  This is a entry level line and only has SATA 2 ports.  I found out exactly the same way as you.  Is the difference noticable at those speeds? *shrug*  At least you'll be able to throw the SSD into your next build.  

I'd like to know as well as I have an 830 sitting idle that came out of my M17x after it tried to destroy it - after permanently nuking 3 OCZ SSDs (the 4th RMA went to a friend who then experience the same in his gaming rig) and then almost killing the 830 I've given up with having an SSD in it and need more reassurance the X51 isn't going to do the same.

SSDs are all well and good with superb performance but a) when they go bad they really go bad, b) are definitely not as reliable as HDDs yet. Regular backups are definite _must_ if you install one.

Just as I suspected! All advertising on the x51 says sata 3 drive !

Could have saved myself quit a few hundred quid in that case.

Feel pretty robbed at the moment. Going to have to have a think about how I proceed.

Actually i loaded Crystal Disk Info and it shows it is connected at Sata 3 6gb/s?

And this is the best AS SSD Bench score i got?

There seems to be something going on, but for the life of me cant figure it out?

It's capping out at sata2 speeds because the intel chipset does not support it.  But as I said before, there's not a huge difference in day to day speeds between SSD sata2 & 3 but a huge difference between the HDD & SSD.  Plus there's not a big price difference between sata2&3 drives, so I'd just enjoy the speed and not worry too much about it.

@Taomyn

Crucial M4's are supposedly a little more reliable vs OCZ.  Perhaps it's a brand quality control thing.  I have both, neither have given me any problems yet.

I don't think it's QA but linked to the use of sleep/hibernate - for some inexplicable reason they, OCZ, cannot support a perfectly standard function of a laptop. If HDD can handle it using SATA specs (as I have proved with 3yrs and zero issues), then so should an SSD, but they can't seem to grasp that concept and try to blame it on the operating system.

Still, maybe once Dell have decided what they are going to do about the wireless problems, I can plan fitting the SSD into it as well. I'd rather only open up the box just the once.

I also have a brand new X51 with the 3rd Generation Core i7 and the Ivy Bridge chipset running with a Samsung 830 and have the same issue.  A super knowledgeable Dell tech confirmed that the new refresh also only supports SATA II speeds.  Unfortunately I feel pretty cheated too and will probably return my system for this reason.

Before I settled on the X51, I chatted with two Dell Alienware techs online who both said that it was SATA 3.  I also called and spoke with a guy in the alienware sales department on the phone who said it was SATA 3 as well as another rep from the Dell Outlet who said it was SATA 3 too.  Many of the reviews of the 3rd gen i7 Ivy Bridge refresh systems all noted that it was SATA 3 as well AND many of the SSD performance benchmarking applications also report the interface as being SATA 6Gps.

Why would you design the X51 system with an extra SATA port on the motherboard that is a different color (black instead of white) with the express purpose of supporting modders who intended to put a SSD in the X51 system and have it NOT be a SATA 3 port.

Here are just a few very reputable websites that reviewed the unit and listed it with either a SATA 3 hard drive or SATA 3 support:

www.anandtech.com/.../alienware-x51-the-xbox-with-teeth

hothardware.com/.../Dell-Alienware-X51-Small-Form-Factor-PC-Gaming-Refined

www.eurogamer.net/.../df-hardware-alienware-x51-review

I also was one of those guys who chose the new high end Core i7 version that said the HD was a 2 TB SATA 6Gbps in my Dell shopping cart for heaven's sake:

Alienware X51 Alienware X51

OPERATING SYSTEM Windows® 7 Home Premium, 64Bit, English

PROCESSOR 3rd Generation Intel® Core™ i7-3770 (8M Cache, up to 3.4 GHz)

OPTICAL DRIVE Slot-Loading Dual Layer Blu-ray Reader (BD-ROM, DVD+-RW, CD-RW)

CHASSIS COLOR Matte Stealth Black with Dark Chrome Accents

VIDEO CARD 1GB GDDR5 NVIDIA® GeForce® GTX 555

HARD DRIVE 2TB Serial ATA 3 Hard Drive

WIRELESS DW1502 Wireless-N WLAN Half Mini-Card

Adobe Reader Software Adobe® Acrobat® Reader

ALIENFX AlienFX Color, Quasar Blue

PRE-INSTALLED SOFTWARE Steam Factory Installed and Steam Extra Content

AUTOMATIC UPDATES 330W External Power Supply

Just as I suspected! All advertising on the x51 says sata 3 drive !   Could have saved myself quit a few hundred quid in that case.   Feel pretty robbed at the moment. Going to have to have a think about how I proceed.

 Sorry you feel robbed. I can understand how thinking you bought something when you didn't can be upsetting

Saying all advertising on the x51 says sata 3 drive is not true. First off the specs page has always listed the H61 chipset and has never listed the SATA ports wether it being SATA 1, 2 or 3. It was never listed and still isn't.

I was unable to find anything stating it had SATA 3 ports from Dell. I also Googled some reviews and other then some user comments I didn't see anyone claiming it had SATA 3 ports. Even if a review did it would be the reviewers fault not Dell's. The system specs page all show the H61 chipset and SATA 2 drive options. And like was said before the H61 is SATA 2. Saying ALL means just that, all. I not only can't find all or some but I can't find any. That's a far cry from ALL.

http://www.dell.com/us/p/alienware-x51/fs

http://www.dell.com/us/p/alienware-x51/pd.aspx

But  when I pick  the $1249.00 i7 3770 config and act like I'm going to buy it the specs on that page lists this.

 2TB Serial ATA 3 Hard Drive i7 3770 configuration

If you pick any of the other configs it just says SATA 3gb/s which we know is SATA 2.

 Same i7 3770 used in this $1099.00 config.

My guess is ether the one config is just a typo or they are stating that the drive itself is a SATA 3 drive. Of course the third option is Dell just upgraded the chipset so it really does have SATA 3. But having a SATA 3 hard drive is not the same as having a SATA 3 port and I can't find anything saying the x51 has SATA 3 PORTS. For as much as I can remember the system spec page for the x51 has always stated it came with the H61 chipset. I can't recall it ever saying anything else. Your CrystalDiskInfo pic showing the transfer mode SATA/600 is for the hard drive. All the info you see there are the specs on your Samsung drive and not the mobo.

If you know of adds stating the x51 comes with SATA 3 ports when it doesn't then you should post them so Dell can have it corrected. If you did see an add stating it had SATA 3 ports and that lead to you buying it then ask Dell to make it right or return it. I know I would if I thought I was misled but I don't believe that is the case here.