M.2 PCIe SSD

I recently purchased an Alienware 17R...awesome power for a laptop.  I immediately upgraded all of the RAM to 32GB, and started searching for an M.2 SSD.

I ended up purchasing a Samsung SM951 256GB M.2 NGFF PCIe Gen3 8Gb/s x4 Solid state drive SSD (2280) card and was intending to use this as by boot drive.  I would have prefered using a 2242 PCIe for this, freeing up my other two 2280 slots for 1TB cards...but I could not find any.

However, my problem and question relate to the computer's inability to recognize the 2280 SSD that I put into the machine.  It's just dead...nothing happens.  It could be defective of course, but that's what I'm currently trying to determine.

I tried talking to Dell Tech Support, but they could not even tell me the difference between a SATA and PCIe SSD, so they were not much help.

I need to know if I can actually use a PCIe SSD in an Alienware 17R.  Do they work at all, or am I perhaps only supposed to use SATA M.2 SSD's in this machine?  Kind of a waste if I can only use SATA drives in this computer though...read/write speeds are crucial for the work I do.

Thanks