1 Pc 2 Ssd. One W/windows 11 Pro, One With Windows 8.1

Geekom mini it13
lexar NM7A1 2tb Windows 11Pro
Samsung 840 1tb Windows 8.1
intel i9 13900H 2.6ghz

Not sure how to ask the right question on running 2 different OS on the computer.
I have 2 SSD ports and the system came with the Lexar and Windows 11Pro.
I plugged my old Samsung with WIndows 8.1 into the other port.
It shows both disks and info
I tried to boot the Samsung 840 during startup using the bios and it doesnt boot. Windows 11 boots
Is there a thread that shows how to run both systems on the same computer?
I have a couple programs I want to run from the old windows 8.1 that won't run on 11Pro.

 

I am not familiar with the bios in that, so can not speak to it. However, I have used Super Grub2 on a usb drive. It see's available boot drives, and lets you choose what you want to boot. It may work in your case. try it and see.
https://www.supergrubdisk.org/

 

Thanks I'll take a look.
When I go into bios it lets me choose which drive but the samsung gives a blue screen and says it starts to repair but then quickly boots to the lexar. I'll try diagnostics on the samsung

 

It's a driver issue. W8 is still "set up" for the machine it used to be on. All the drivers are for the old system board, etc. It can't boot on the new machine. If you pull the W11 drive, and just leave the W8 drive in, you may be able to use W8 install media to reinstall it to the new machine. However, this opens up a can of worms, like apps and data being wiped out. It may be possible to clone the current W8 drive, reinstall 8 on it, then MIGRATE the OS over to the fresh install from the clone. Cloning it back will just leave you with the same problems.