I've got an old (late 2006) Mac Pro Quad (2 x 2 x 2.66 gHz) Xeon 3GB RAM with a Nvidia 7300 GT (256 MB video ram) that is running out of steam (mostly when it comes to Flight Simulator FSX on the XP side). Still running OSX 10.4.11 but I could switch to 10.6.xxx if I have to. I've been through this MacRumors post related to graphics card upgrades: http://forums.macrumors.com/showthread.php?t=410804 but its last post is in July 2008, so I can't be sure if there is anything more recent related to card upgrades. So the question remains: Is there any good, simple, easy way to upgrade the graphics (512 MB at least) or do I have to buy a new Mac Pro? Thanks for any advise (and commiseration).