Hi @China Blue  welcome to this user to user discussion forum. This is not Dell Support. 

Dell Support for Alienware m15 R3 Setup & Specifications, Storage says all the M.2 slots have PCIe Gen3 x4 NVMe interfaces, the Two M.2 2280 slots capacity is up to 2TB and the One M.2 2230 slot capacity is up to 512GB. 

Do not get your OS(C:) to use RAID 0, which shares data equally between two identical drives. A single M.2 NVMe has equal performance. 

Your 235GB OS(C:) drive should be cloned (copied) to a single 1 or 2TB M.2 2280 drive because their read/write speeds are usually faster than their lower storage capacity drives. Having selected the make for your solid-state drive, you may wish to check the advertised read/write speeds of all their drives, because they may offer fast and ultrafast drives. If you are going to use m15 R3 for gaming, get the ultrafast M.2 2280 PCIe Gen3 x4 NVMe drive. Then look on their webpage for the free cloning application and its instructions. 

The other M.2 2280 slot can be used for creating OS(C:) clones and also as a storage only PCIe Gen3 x4 NVMe drive. The M.2 2230 slot is usually ignored, except when the maximum physical RAM is not sufficient, and invoking the Windows 10 option to have virtual RAM. 

Please click on Kudos to say thank you for response from another user. Please share an update on progress, so that other users derive benefit from your experience. Thank you. 

Hey Crimson,

This is very helpful in clarifying what I need. Thank you for the detail.

So is am I correct to understand that the SSD replaces the HDD? If so after cloning the SSD should I remove the HDD?

TY!

Hi @China Blue  thank you for sharing update. 

Your opening post says "In reviewing how to install the memory there was a mention of cloning. I thought that was for a hard drive.".  Please note that the m15 R3 does not have a HDD.

We are creating a clone (copy) of your small 238GB SSD boot drive onto a larger capacity 1 or 2TB M.2 2280 NVMe drive. The small 238GB SSD boot drive is then removed, so that the 1 or 2TB M.2 2280 NVMe becomes the new boot drive.

Hopefully, this the clarification that you wanted?

Backup, the OP has the 2016 released 15 R3, not the 2020 m15 R3. So not sure if you need to change anything.

Hi @China Blue   the forum moderator says your system is the 15 R3. The Alienware 15 R3 Storage options include a HDD, so now we just need to revisit our understanding of the OS(C:) boot drive. Perhaps your system has a HDD and the M.2 Slots have a solid-state drive. Please remove the base cover and have a look. It would be great if you could post a photograph, so that users can see what you see. Thank you. 

Hi @China Blue   if no camera, is this what you see?  Please reveal your OS(C:) boot drive. Thank you. 

Hey@crimsom I am moving this week so my tools are all packed up. Tell me how I reveal my OS(C:) boot drive. I will respond with a picture by weeks end (hopefully).

Ty

Hi @China Blue  I am sure you can work it out for yourself. Its not as if you have paid for assistance. 

@crimsom,

Finally I am back! The picture you supplied is the same as my laptop. Is the large rectangle on the lower right with the colored bars on top and bottom the hard drive? If so can you direct me to instructions of how to clone from the hard drive to SSD? Also after cloning and installing the SSD should I remove the drive?

Thanks for your patience.

Hi @China Blue  please click on start button (in bottom LH corner) and paste Diskmgmt.msc into Search, wait for automatic refresh, then right click on diskmgmt.msc at the top, and Run as administrator. When Disk Management window opens, move the transition upwards (see image) so that all drives are shown. Use key combination of shift + windows + s to capture and save image. Please share this image, thank you.