I just bought a new Metabox laptop with no pre-installed OS. I downloaded eOS v5.1.5 and installed it on the laptop with no issues. However, when I booted the laptop for the first time after installation (and each time thereafter), it gets to the login screen (I see my username, background, etc.), I enter my password, then after a few seconds of a blank screen with just the cursor, it displays the 'e' logo then shuts down.
Interestingly, I've noticed that it also happens when using the 'try' feature of the live USB (computer shuts down before booting to the desktop). However, doing the same thing with Linux Mint (running it off the live USB) doesn't have any issues (I can boot to the desktop fine).
The only thing I can think of is drivers. But the issue is I'm on a public wifi that requires a login via a webpage to connect (so I can't download drivers during the installation).
UPDATE: I've since tried installing Linux Mint 19 on the laptop, and while it installed and booted ok (though without wifi), it did eventually freeze up and then try to shut down (similar to what happens with eOS).