Did you partition the drive correctly? There is a possibility that you installed mint incorrectly.
Try legacy boot option.
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Did you partition the drive correctly? There is a possibility that you installed mint incorrectly.
Try legacy boot option.
Just had fun with this with my optiplex 790.
Things I have found:
If you are using the front USB ports try the lower ports.
Make sure that you have formatted your live USB properly.
On boot press F12 to get the one time boot menu, if everything is right you should get a menu that gives you legacy boot options with UEFI boot options below that.
The big thing here is that not all live distros appear to work with the Dell UEFI implementation (got Linux Lite and Manjaro working)
My Optiplex 7060 defaults to RAID mode for SATA drives when there's a drive in the M.2 slot. Maybe yours is set for RAID too?
Turn off secure boot? Turn off UEFI? Just try reinstalling?
Also, does it work if you boot the USB and choose "boot from first hard drive"? That'll tell you whether it's the Dell boot thing or a problem with the install.
Does a liveUSB boot ?
Yes.
Make sure it's in AHCI mode and not RAID. It's probably a setting under storage, at least on newer ones it is.
Tried that already. Didn't help.