Hi, 

The Aurora R4 supports Quad Channel DDR3 2133 MHz XMP, 8 GB to 32 GB (four slots).

Lot of people tried updating to 4x4GB and 4x8GB at 2133, but with no success: excluding some exceptions all of them working at 1600mhz or not working at all

I need advice form people that had success in 4x4GB 2133 config about what module part number is able to achieve those speeds.

You could also try posting this on the Notebook Review and Alienware Arena forums for this information. 

Hi there,

I have aurora r4 i7 3930K. I wanted to upgrade to 4x4GB and bought G.Skill 4x4gb 2133mhz quad channel sticks. It took me a week and lots of trouble to get to where I am now. I got them working but unstable at 2133mhz so now they run at 1600mhz until I find a better solution. I mismatched first so that the bios would go to xmp mode but it went unstable. I do not understand why does dell not give us tested profiles so we need not bother with manual experimenting but overclock easily!

16GB 2133MHz PC3-17000 was never validated by Dell. We only validated 8GB PC3-17000 (4x2GB). We tested/validated our Dell OEM memory below =

6CY34 2GB, 2133MHz, PC3-17000, Non-ECC, DDR3, 256x64, XMP, Kingston
9W02G 2GB, 2133MHz, PC3-17000, Non-ECC, DDR3, 256X64, XMP, Patriot

For our 2133MHz XMP ram, you must go into the Bios -Advanced -Frequency/Voltage Control -Extreme Memory Profile and choose Profile 1.