Re: 3 questions:

1. I want to have both drives, so there has to be other spots for the 2nd SSD?

motherboard has only one M.2 ssd slot. To install 2nd M.2 ssd you need a PCIe adapter.

https://www.dell.com/support/manuals/en-us/alienware-aurora-r10-desktop/alienware-aurora-ryzen-service-manual/system-board-components?guid=guid-6e125091-884c-4dd9-8546-013747e2d1d0&lang=en-us

2. Is there an easier way to do this that doesn't require taking out the GPU and other pieces? Like using the SATA empty spots (I think?) at the bottom of the case?

Service manual recommends you remove gpu first as applicable before removing M.2 ssd. Long gpu overlies the ssd on motherboard so you have to remove it first.

https://www.dell.com/support/manuals/en-us/alienware-aurora-r10-desktop/alienware-aurora-ryzen-service-manual/removing-the-solid-state-drive?guid=guid-2fdd0ff0-61c1-4661-85bf-206fb411f5ba&lang=en-us

3. Do I need an adapter like this I found from another post?

Yes if you want to install two M.2 ssd.

"Is there an easier way to do this that doesn't require taking out the GPU and other pieces? Like using the SATA empty spots (I think?) at the bottom of the case?"

Yes, you can install a 2.5" SATA SSD in one of those slots and plug it into the SATA header.  You cannot plug an m2 nvme pcie ssd into a SATA header though.  You'd need a SATA M2 for that.  But cheaper to use a 2.5" SSD, plus the 2 5" caddies are already mounted and ready for use 

Example of a 2.5" SATA SSD:

https://www.amazon.com/Crucial-MX500-NAND-SATA-Internal/dp/B077SF8KMG/

Yes, you can install a 2.5" SATA SSD in one of those slots and plug it into the SATA header. You cannot plug an m2 nvme pcie ssd into a SATA header though. You'd need a SATA M2 for that. But cheaper to use a 2.5" SSD, plus the 2 5" caddies are already mounted and ready for use.

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This is what I usually recommend to people.

After all, (in this example) the system already has a super-fast 512gb M.2/NVMe SSD for:

- All Windows-10 stuff
- All Programs and Apps
- Several of your favorite games (even large-ly installed ones). Remember that Steam can have more than one installation folder (one on C-Drive, one on D-Drive, etc.)

... Anything else you want to load onto this system should run fine from an inexpensive 2.5in SATA-3/600 SSD. It is still very fast (still 4-times faster than a conventional spinning-platter hard-drive).

Thanks.. that's the backup plan since as I said I unfortunately already bought the M2. So if I can't figure out how to install that with the adapter, I'd have to sell it at a loss and buy a 2.5".

Thanks! For the adapter, what do I need to check to see if it's doable with my system? I guess just have to open up the computer to see if slots 16 and 17 (the PCI-Express x4 slots, not the x16 on slot 15 and 18, which one of them has the GPU on it)? I read in another post that the 15 to 17 are all covered by the RTX 3080, so if that's true, there is no way for me to add this second M2 or I then have to use a x16 adapter?

The gpu comes stock in the top slot, the only way the lower x16 (x8 electrical) slot would be obstructed in oem configuration is if you had sli or a liquid cooler for the gpu (which I don't believe is offered for the 3080 yet).

You can stick the x4 m2 pcie adapter into the lower x16 slot.  It will work fine.

The x16 m2 pcie adapters are for multiple ssds and require bifurcation which isn't supported with the r10 bios.

Oh actually I did add the liquid cooling option when I was purchasing: "Dark Side of the Moon chassis with High-Performance CPU Liquid Cooling and 1000W Power Supply"... not sure if that is what you meant?

At this point, I'm leaning towards returning the M2 and buying a 2.5". It will come to about the same price but with much simpler installation (and much lower speed of course).

Thanks a lot for the help!

Have you had any luck yet i have a r10 and im in the same boat i wanna put another ssd in but i just feel like its so complicated with the nvme m.2's on the r1 should i just get a normal ssd