Triple boot Windows ubuntu and other distro like PCLinuxOS

#1
Earlier with the help of this forum I was able to install windows 7 on second hard disk and windows xp and ubuntu on first.Now that I have small partition getting free I wanted to install PCLinuxOS so as to test my ATI Radeon HD agp card since I failed miserably getting the driver to work in Ubuntu.To cut the long story short my attempt in installing PCLinuxOS in the spare partition ended in fiasco losing grub and was not able to boot to any OS.Not knowing what to do I reinstalled Ubuntu.
Hence I request a step by step tutorial like your earlier "Dual booting ubuntu linux and windows 7".
Hope my request will be looked into
thanks