[strike]If you're asking what kind of memory the 940MX is using, that would be 2GB of GDDR5 memory (VRAM) which is a current specification of video memory. DDR3 (RAM) is a previous generation of memory that is used on motherboards. Your laptop should be using DDR4 RAM though.[/strike]
bignastyid :
The lower clockspeed(1020Mhz) of the GPU indicates the DDR3 version of the gpu. The GDDR5 version uses a clock speed of 1122Mhz.
http/www.notebookcheck.net/NVIDIA-GeForce-940MX.156033.0.html
Possible but they are also reporting a different clock speed. You mat need to contact Dell and see what they say as they have access to documentation on the system that we do not.