32- and 64-bit have nothing at all to do with "computing power". They only affect how much memory a process can take advantage of. 32-bit applications can practically address a maximum of about 3 GB of RAM. A 64-bit process can access a theoretical maximum of 64 petabytes of RAM--64 million GB. As the issues with X-Plane's clouds are all tied to harnessing GPU power, 64-bit won't do anything. What 64-bit will do is allow X-Plane to store much more texture memory, which means version 10 will finally be able to run with high objects, his texture res and lots of custom scenery without crashing. edit: you probably already own a 64-bit machine. Almost any processor made in the last six or seven years will be 64-bit. My eight year old G5 has two 64-bit processors.