My Acer 5315 laptop is running Windows 7 64-bit version with no problems so far. I have 2 gb. According to Acer when I ran Vista or Xp the maximum amount of memory supported is 2 GB. Will the Windows 7 64-bit operating recognize 4 gb and run without any problems. I once tried 3 GB running Xp and although the bios recognized 3 GB it didn't work properly so I replaced the memory with 2 GB of ram. My laptop has a T7500 2.2 GHZ cpu Will XP mode work with this processor ?