Area 51 R2
Alienware 17 R3
Alienware - Area 51 R4
I have been wondering about that as on every bios update I get two offers: and R4 and an R5 but I always stick with R4
I ran cpu-z version 1.87.0.x64 and stored the results as a text file here
Feel free to download the text and run "fc" compare to your own cpu-z report. pm me the difference or pm me your report maybe we can figure out what is different.
Be nice if a dell engineer would speak up about this.