I bought a Dell SC440 for Jade Systems (that's me). I'm setting it up as a virtual host so I can create virtual computers at will. I've decided to try XenServer, I think mostly because the free version is just a license-key upgrade to the full version. Besides, I already have some experience with VMWare, albeit second hand.
I had to F2 into the BIOS on initial boot of the SC440 to turn on virtualization in the CPU. It was relatively easy to find on the menus, but not right at the top level (My apologies for the vagueness here. The servers are in another room, so I wasn't blogging while I was installing).
The install of XenServer 4.0.1 went exactly according to the instructions. I read through the four pages of documentation first, and so I had all the answers I needed -- the usual network set-up, which time servers to use, etc.
I just finished installing the security patch. First challenge: actually getting the file to the XenServer host. I put a DVD in the DVD drive, but there's no entry for CD or DVD in /etc/fstab. The installation instructions recommend using a USB key. I flailed on that for a while, Googling for Linux-for-dummies level help on USB, before I said to myself, "Right. I guess I still have to be a Linux sysadmin," and found the appropriate dev to mount the dvd. From there it was maybe a minute to install the patch.
Total time: About half an hour to install XenServer the other night, mostly unattended after the usual initial Linux questions, plus 45 minutes now, mostly Googling.