Hello. I am currently trying to upgrade my Dell Optiplex XE. The computer right now has a Intel core 2 duo E7400 which is a dual core cpu at 2.8ghz. I am trying to upgrade the CPU but I don't know which one is compatible. Do you guys have any suggestions? I was looking at the Q9650 http://www.cpu-upgrade.com/mb-Intel_(chipsets)/Q45_Express.html since the PC has a Q45 chipset. Thank you!