XPS 8900, can you use NVMe drive to boot

Thank you. I had searched, but your search was better.

So I've read thru them. It seems you can indeed use an NVme or other M2 drive in the M2 slot as the boot drive, but there will not be much, if any, speed advantage over using an SSD on a Sata iii port.
Can you confirm? if if I am not understanding correctly, educate. Thank you.

other note, in my disk manager, the current 32GB drive in the M2 Slot 2 does not show up in Disk Management. It is active in the Bios/setup menu.

Thank you for the help.

@tvaudioman I think there is a speed advantage to using an SSD on the SATA III port. PCIe x1 is 250 MB/s, x2 is 500 MB/s, and so on. On new PCs, I believe the typical M.2 PCIe/NVMe slot is x4. SATA III is 6 Gbps or 750 MB/s. So, if I calculated correctly and assuming that the SSD is limited by the interface, an SSD connected to a SATA III port is faster than an M.2 SSD connected to an M.2 slot that is PCIe x1.

I think your 32GB SSD was used as a cache for the hard drive. I am not sure why it does not show up in Disk Management, perhaps it has been wiped (partitions and data removed).

The cache 32-GB is not supposed to appear in Disk Management. The user isn't supposed to be able to do anything to that drive so it's hidden. Windows considers it to be part of the boot C: drive.

You will have to do two things in preparation for a new SSD:

1. Disable the cache in Windows and reboot before removing that 32-GB SSD or Windows won't boot from the HDD again.
2. Do a few simple steps in Windows before changing BIOS from RAID to AHCI after the cache is disabled, before the new SSD is installed, assuming you'll clone the current boot drive, rather than doing a clean install on the new SSD.

As for speed/performance, Crucial (for example) sells  a 500 GB NVME SSD with 3400 MB/s Read, 3000 MB/s Write for the XPS 8900, but their 500 GB SATA SSD for the XPS 8900 is only 560 MB/s Read, 510 MB/s Write. So an M.2 NVME should perform better/faster than a SATA SSD.

@RoHe wrote "So an M.2 NVME should perform better/faster than a SATA SSD." The M.2 NVMe should perform better/faster only if the interface will support it at its maximum speed; the issue is that I don't think the interface in the XPS 8900 will support it. 

Thank you.
From what I've read, the M.2 slot on the 8900 is limited to 1 lane, so slower than SATA III.

I plan to do a clean install to a new SSD, and keep the other SSD as it is, for now. (going thru it for a widow).
If I'm doing a clean install, do I need to mess with the 32GB-SSD, or will it just do it's think automatically, in the background?

Thanks for the help.

@tvaudioman  - If your intention is to keep the old HDD around, you should break the cache with the 32-GB SSD and configure Windows to use ACHI before doing anything else. That way you could still reinstall this HDD and boot the XPS 8900 from it.

Once that's done, physically remove the 32-GB SSD and leave BIOS set to AHCI for the clean Windows install on a new (SATA) SSD.

And while you're in there, this might be a good time to install a fresh motherboard battery, CR2032, 3-volt coin cell battery, ~$2.

Hi, 9 months later I happened to run into your post.  In case anyone else has this same question, I just finished upgrading my XPS 8900 to a 1TB Samsung 970 EVO Plus NVMe M.2 drive and it's speeding along at 3,400MB per second. Amazing!

I had a 250 gig m.2 Samsung 850 EVO boot drive but I was running out of space.

You need to get an adapter (here's mine, they're cheap https://www.amazon.com/gp/product/B07GFDVXVJ ) for using one of the PCIe slots on the motherboard (assuming you have a spare one - most people do).

The free Samsung data transfer cloning software is super simple to use.

That way, you'll get full speed because that slot has 4 lanes.  The m.2 slot only has 1 lane.  You can easily make the 8900 boot to the PCIe slot and you're off and running at blazing speed!

Hope this helps.

Tony