FORMATTING SSD FROM BIOS INSTALL

It will also probably offer you to create one (or more) partitions on the now formatted and fully available drive, with partition size(s) of your own choosing. Nevertheless my guess is that Win10 will most likely just go ahead and use GPT partitioning on your second M.2 512GB drive if it actually does kick in to make you the offer to format it. GPT is only REQUIRED if you are using a drive larger than 2TB, and also if you want to allocate a partition larger than 2TB on a drive larger than 2TB. With your second 512GB M.2 NVMe drive it really doesn't matter whether you opt to use MBR or GPT, since either will work on such a small drive. In order for a drive to be usable for one or more 'partitions' it must be formatted for use either using (a) the older more limited and restricted MBR partitioning method, or (b) the newer essentially unlimited and unrestricted GPT partitioning method. On the other hand, if Win10 does recognize the presence of the second 'raw' drive available for use and offers to let you format/partition it, go ahead and accept that offer. Just ignore the second M.2 drive which is not yet available. Just continue with your regular first-time Win10 startup process and configuration. As such it may be seen by Win10 the first time you power on the machine as unavailable for use, and no drive/partition letter (like D, or E, etc.) will automatically be assigned. It will probably be 'raw', completely unprepared. (3) I don't believe your second M.2 drive will come pre-formatted and/or pre-partitioned. It will simply be a second drive, which you will 'purpose' yourself as an ordinary 'data' drive. You don't have to worry or do anything about that issue. So when there is a second M.2 drive discovered it will automatically be handled by the BIOS and hardware in non-RAID mode.

And the machine is already configured for non-RAID operation. (2) Since your P51 was purchased from Lenovo with one M.2 PCIe NVMe drive already present, the Win10 OS has already been installed correctly onto it. But you will need a fastening screw for sure to secure that outer end of the tray down to the M.2 bay.

I don't know if that screw is included in the hole on the P50/P51 by Lenovo from the factory even if you don't buy a configuration that includes an M.2 drive or not, or if that screw is included with the M.2 tray part itself. Note that there is a fastening screw required to hold the adapter tray down securely into the M.2 bay. And if you opt to use the space for two M.2 drives then two adapter trays must be used to hold the two M.2 drive securely. So the physical space is sized to hold either situation. This tray for M.2 drives is needed because the physical space occupied by the two M.2 drive bays in the P50/P51 can be used instead for a single 2.5' drive if you want.

FORMATTING SSD FROM BIOS INSTALL

(1) To install your second M.2 PCIe NVMe drive you need the M.2 drive bay tray part 4XB0K59917 which you can obtain from a variety of sources for about $10-$15. D, E, F, etc., and you will also be allowed to changed those letters later if you decide you don't like what you originally opted for. You will be able to assign 'letters' to those partitions, e.g. You can opt for one large partition using the entire available space on the drive, or you can create two or more smaller partitions each with whatever size you want, whatever you care to do. Each partition you create must be designated to use a 'file system', which you should choose as NTFS. The drive itself must be 'formatted' using either MBR or GPT partitioning techniques. You can create one or more 'data' partitions on it, and they can be given letters of D, E, etc., or any other letters you might want to assign to them for your own reasons. Once formatted it will provide somewhat less than 512GB of actual partition space, which is perfectly normal. Just use it as an additional 512GB 'data' drive physically separate from your primary 256GB 'Windows' drive. You don't need RAID, and with two differing size drives you really couldn't use it as RAID-configured even if you wanted to. Adding a second M.2 drive to your P51 for 'data' in a non-RAID configuration is about the simplest thing you can do.

Formatting ssd from bios