Preparing a Linux-on-a-stick and running it? Using either your working RX580 or GTX770, do the following:
First of all, set a USB stick aside for this process. It'll be formatted, so make sure not to lose any data.
Second, download a Linux distro image. I'll link
Ubuntu here as it is a baseline distro, and plenty for what we'll need.
Third, download
Rufus. It is the software we'll use to create a bootable drive.
Fourth, use Rufus to create the bootable drive. First, you'll select the USB stick you'll use at "Device". Then, Click the "SELECT" button and open the Linux image you downloaded. Then, at "Partition scheme" select
MBR. Leave the rest at default and click the "START" button. It may then ask some files that it'll download on its own, and if you want to use the ISO or DD Image mode. Select ISO and confirm (DD works even better, but leaves the stick unusable for anything else unless you reformat its partition table).
View attachment 338187
Fifth, after Rufus finishes (it takes a little while), shut your PC down.
Sixth, swap the GTX1660 in, power your PC on, enter BIOS options (DEL key), set BIOS mode to Legacy and select your USB stick as boot drive. Save and exit.
Seventh, if you get to an Ubuntu menu, we're already doing progress. Just start Ubuntu (I don't know how the option will be explicitly written, but it's the default and will be executed on its own within a few seconds).
Eighth, if Ubuntu starts and shows open the Terminal and type in the following command, which'll show if your card is reporting correctly to the system.
If this process is succesful, your card may be saved. But that's for later.