Steve Davidson wrote: MCHK??? Could this be "Machine Check"? If so I would try booting something else up to see if it also fails. -Steve Anyone have experience of installing Ultrix? I tried to boot off the Ultrix VAX 4.4 CD but got an error after a while, something like MCHK. Any ideas? Do I need to provide some fancy boot flags? This is onto a VAXserver 3100/95. Regards, Mark. OpenVMS runs fine... although I suppose I should try booting OpenVMS from CD to be sure.