I understand that Flex does not support pure 64bit machines,
but is says that it supports 64 bit that runs in 32bit mode...
As I'm thinking of buying Windows 7, and don't know whether to buy 64bit or 32bit.. please help me understand
1. Is running in 32 bit mode means I need a different installation of Flex, or do I need to operate my machine in a mode that supports only 32 bit?
If latter, why would buying 64bit machine for Flex dev in the 1st place?
2. Is that applies to Flex 3 also? if not, to which versions?
Flex is the framework. It runs in anything that runs Flash Player. It doesn't care or even know about 32/64 bits.
FlashBuilder is the IDE that you use to create Flex apps. It runs inside Eclipse. Both are 32-bit applications, but work perfectly well on Windows 7 64-bit .
If your PC supports it, definitely go for 64-bit. It will maximize the amount of memory available to Flash Builder and make everything run smoother & faster. Only very old or badly written applications & drivers will have any problems.
BTW: when you buy Windows 7, you get both 32 and 64-bit versions in the DVD box.
I've used Flex 4.5 and 4.6 and Flash Builder on my Windows 7 64 bit machine with no issues at all