Thanks for sticking with this thread Pyree. Through a series of unintentional events I discovered the culprit. I was trying to install Microsoft Word, when I realized it wouldn't install because I didn't have Windows Vista SP1 (which was an honest mistake.) I realized my Windows Vista x64 Ultimate build was 6000, when it should be 6002. I downloaded SP2, realizing I need SP1 first. So just last night after I installed SP1, Vista is now showing the proper 4.00 gb's. I hope anyone who comes to this thread can get some help out of this, as I was starting to really get frustrated!