Alienware 17 R3 Ram upgrade 32gb 2666 mhz?

Hi grothmog‌,

This is the supported memory for your model:

You add 2 Specifc Modules from Crucial that are guaranteed to work for your system.

Adding faster ram DOES NOT increase performance.  Standard transfer rates are  2133 and 2400 MT/s

with the actual rate based on the CPU and CHIPSET.  Most are LOCKED to a specific FSB.  INTEL XMP is not an option.  Ballistix Sport LT 16GB DDR4-2400 SODIMM Alienware 17 R3 for CT8072009 

Amazon.com: Ballistix Sport LT 32GB Kit (16GBx2) DDR4 2400 MT/s (PC4-19200) SODIMM 260-Pin - BLS2K16G4S240FSD (Gray): C… 

http://www.crucial.com/usa/en/alienware-17-r3/CT8072009 

• Maximum Memory:32GB
• Slots:2 (2 banks of 1)

• Upgrade for: Alienware Alienware 17 R3
• Crucial part number: CT8072009
• Brand: Ballistix
• Form Factor: SODIMM
• Warranty: Limited Lifetime
• Specs: DDR4 PC4-19200 • CL=16 • Unbuffered • NON-ECC • DDR4-2400 • 1.2V • 2048Meg x 64

High Speed RAM - Is it Worth it? DDR3 1333MHz vs 2400MHz Test - YouTube 

Does RAM speed REALLY matter? - YouTube