First: Thanks for your always quick replies. This is encouraging! A normal boot with usb-stick plugged in. The result is in "boot messages.txt" Then a boot without the stick. Kernel freezes, but remains boot after the stick is plugged in. Look into "boot messages plugged in later.txt". It looks like a resume/swap-partition thing. "hwinfo --full" has no result. See "hwinfo.txt". So I tried it with YAST: "YAST-hwinfo.txt".