Question Just installed new MOBO, can only access one of my SSD's

Feb 21, 2021
Currently using an MSI Z490 gaming edge wifi board, intel i7 10700kf CPU. I can only access one of my SSD's after switching the BIOS setting from UEFI -> CSM. The other two ssd's are showing up on the bios, but cannot be selected or made boot priority. I think it may have to do with them being stuck in a legacy bios mode. When I launch my computer through the one working SSD, it shows the ssd's there on the computer panel screen, but clicking on them only reveals a single blank bootsqm.dat file. I can't figure out how to change the BIOS boot mode on them, and i'm wondering if it will be quicker to just wipe the SSD's and start over fresh (mostly just games and stuff on them that I dont really need. Anything important is on my main SSD (thats running) or on cloud devices.


Win 10 Master
Did you clean install win 10 on the new PC?
that could be part of the problem.
if only 1 of them has windows on it, the other 2 should still show up for it if you log into it.
You don't need windows on all 3 drives, just one.

remove all ssd except the one you want to install win 10 on
reset bios to defaults to not use CSM mode.. UEFI is more useful going forward. Max size hdd isn't 2.2tb, no limits.
download the Windows 10 media creation tool and use it to make a win 10 installer on USB
boot from installer
follow this guide:

once win 10 boots from the ssd, unplug PC and reattach the other 2 ssd. If either had windows on it before, make sure they not showing in boot order.