I’m installing CentOS 5.5 on an old Dell E521 in the hopes to use it for my new media server. The first time I booted to the CD, I was presented with the normal Disc Boot Install options of running it graphical or text. I chose graphical, and the system halts at a line that says: “Enabling HT MSI Mapping”. I waited 5 minutes and there was no movement, so I restarted the system and was back at the Disc Boot Install screen. From here, I decided to type in “linux noapic” and the install has gone through. Just a little tip!