I have been using crucial ram for six years now, I have one machine with 2GB runningXP Pro and my other machine has 3GB running Vista Ultimate. The XP machine is muchfaster, with only a 2.8GHZ intel P4 while the vista machine is running a 3.2GHZintel P4. The more I use my vista machine the more I like it. I give it 5 starbecause it performs well for me.