(In reply to Stefan Dirsch from comment #1) > Please try with out KOTD. > > https://en.opensuse.org/openSUSE:Kernel_of_the_day Thank you for your reply. The problem solved: monitor detected properly and the resolution is at it's maximum. (The trick with two kernels described at the KOD page didn't work, older kernels were deleted with Virtualbox with them). Best wishes, Piotr.