Well, considering he didn't change anything other than installing Poser, I would say he did eliminate other possible culprits. It's pretty simple really: Boot takes x seconds - Install Poser Boot takes y seconds - Remove Poser Boot takes x seconds If poser doesnt have any affect on boot, then x should equal y. However, if i recall correctly, Poser does require a reboot after install to complete its setup. Right? Therefore, the only way to truely see if Poser increased boot time would be to perform two reboots - one to complete the setup, and another to check the time your system takes to boot up.