Question thinkpad boot OSes permanent?

[devtinagub1]

had this t470s for about 4 years maybe and its my goto for testing different operating systems so it seen at least a dozen+ and they all still reside in the boot menu when i hit f12 for boot from other device even if they are old bygones. the problem is i cant tell any more which is which that i just installed for testing many have the same name but dont differentiate with the version number or even seem to keep a install order or something helpful like that. anyway what in the world can i do to get rid these they dont reside on the drive it must be a chip and ill bet it isnt easy to fix.

 

[NedSmelly]

Sounds like either the EFI partition (if UEFI + GPT drive) or Master Boot Record (if MBR drive) needs to be reset.