I have a new desktop coming with the Newhalem quad core and 12 GB RAM. No problem here as I will have Vista 64 Business installed.The question is my Dell M90 laptop with 4 GB RAM. I have Revit 32 on it with Windows XP Pro. Is there an advantage to installing Vista 64 Business and Revit 64 on the M90? I'm not sure if any upgrades to the M90 are possible, or how expensive, but that could be a possiblity.Also, I will be transfering everything to the new computer from my old desktop and plan to use the old one for my Wacom cintiq to work in Photoshop and Painter, but Revit 32 will still be there. My guess is that I can only have Revit on two machines per the license agreement. Is that true and does that installation of Revit become null after I authorize Revit 64 on the new machine?It seems from other threads and Wes' treatise on the subject that Revit files produced on both versions should be compatible. Comments please!!