Well Woody005, that would depend on where in the world you are from.

All the cards listed are the range I've found available in Europe.  In the Americas, I only seem to be able to find the MSI (well within the size requirements) reference design and two other reference cards by POV/Trooper which have no sizing information as yet.

If you're in the UK, I'd recommend getting the PNY card from Scan.

So I have a AW X51 R2 with the GTX 745 4GB and an i5 440k (not compleatley sure about the possessor number but it has 3.2ghz) anyway I was wondering if I can use a GTX 960. If so which one MSI, ASUS, EVGA? Could you provide a link? I was curently looking at this one: amazon.com/MSI-Computer-GTX-960-2GD5/dp/B00SAYDRKS/ref=sr_1_2?ie=UTF8&qid=1423677891&sr=8-2&keywords=msi+GeForce+GTX+960+2GB

Thanks  so much!!

-Michael Pinto

Awesome, you can get the adapter easily, also, do I need to underclock? could you please give me the link to the PNY one, Where did you buy yours?

Depends on your psu. If you have the 330w adapter then yes , it should work w no problems. The one you picked should be fine. However, i recommend the PNY version since that's the one i have and it works beautifully

What I did was put a nice looking modular power supply next to the box and had the one PCI cable going to the graphics card into a hole in the case

Do you know if it will work with the dual fans or will they take up too much power? 

MSI GTX 960 2GD5T OC GeForce GTX 960 2GB 128-Bit GDDR5 HDCP Ready SLI Support ATX Video Card this graphic card. thanks. 

As well my alienware x51 is an r1 but i have a 330watt power supply so can i still get a gtx 960 in and it will work?

Here you go:

www.pny.com/gtx-960-2048mb-gddr5-pcie3-graphics-card

EDIT: Make sure you have the 330W PSU.

One more thing how do you know if the gpu you are buying is a blowout syle fan?

This is a horrible idea due to the tiny case. You need a fan designed to blow the heat OUT of the case, not inside it. Definitely get the PNY blowout style fan, or any blowout style fan version. I can only recommend the PNY one, since it works beautifully w my alienware x51 r2

Can you link the gpu you got thanks

The easiest answer is to just look at the picture and the design of the gpu i linked. If it looks like that, it's  a blowout style

I allready ordert a gtx 960 4gb evga and got a 240w power supply , i hope it will work!

just beware the 4GB GTX 960 from EVGA come with 8 pin PSU jack (75+150W) and that the Alienware has only supplied 6 pin connectors.

You can upgrade tio the GTX 960 safely without any potential problems. In fact they are now selling the x51 with the GTX 960 only.