Hi Esther

I did some research- we should be able to run 64 bit apps after all- what we can't do is run the whole OS in 64 bit mode- I think! Something about Apple not creating a 64 bit "Kext" for the old MacPro. But hackers might get around that. I have an ORIGINAL G3 233 that I upped to a G4 466. Apple decided that OSX 10.3 SHOULD not be installed on computers without built in USB. So a hacker wrote a program that turned off the code in the installer that looked for built in USB. I installed 10.3 and 10.4- no problems

   Anyway-I keeo reading that the Radeon 4870 which Apple does not sell for the MacPro1.1 works GREAT= in OS 10.5.8 and 10.6.3  Hmnnnnn......