I don't think this has anything to do with 64-bit processing. Version 3 was designed to run under Mac OS 9 or earlier, and it CAN run under the Classic emulation of Mac OS X - but but NOT on an Intel Mac or under OS 10.5 and later.
The earliest version to run natively in Mac OS X is 5.5.
OK here is more info I'm working on a new gateway laptop PC with windows 7.0 with new Bit processor. tried to load FMP 3.0 windows 7.0 would not load so I'm trying to find out what version of FMP supports Bit processor on WIN 7.0. Then will this new version be able to open my older data base from FMP 3.0? Thanks in advance for any help!!!
Oh, you're talking about Windows... I'm afraid I don't know much about that, though I think you could still run your current version under Windows 7 in Windows XP Mode.
In any case, the current version of Filemaker can open (actually, convert) your .fp3 file/s, so at least your data will be there. As for functionality, it depends on the complexity of your solution: some converted solutions are ready to go, some require minor tweaks and some are candidates for a rewrite from scratch. You would do well to read the migration white papers available from Filemaker, Inc.