Inconsistent USB BOOT in X200S

[TYR]

Just trying to install Linux on my new X200S. Blocker problem: although the BIOS menu under F1 > Config > Startup shows USB BOOT to be Enabled and USB HDD as the first item in the boot priority list, marked + as being bootable, attempts to boot from it fail silently (going straight to Windows).

Here's the interesting bit. The boot menu under F12 shows the USB drive as being 1 in priority, but suffixed with - and therefore marked as non-bootable. Selecting it causes the machine to briefly light up the USB and then boot Windows, same behaviour as just booting it with the USB install disk inserted without further intervention.

Problem is the same in Quick or Diagnostic boot. Nothing seems to be logged.

[Originally posted in the X2/X3/X4 forum by mistake]

[twistero]

Well... If it always fails, where's the "inconsistent" part? Seems like a non-bootable USB drive to me.

[jdrou]

Yes, first thing I would test is whether you can boot that media on another machine.