Quartus 7.2 to 9.1

[Altera_Forum]

I am currently running Quartus 7.2 SP3 and would like to upgrade to 9.1 with the ability to use 7.2 intermittently. Is this possible, or does the 9.1 install remove 7.2?

[Altera_Forum]

Should be possible. I can't think of any issues. At some point (I can't remember if it was 7.2 or 8.0) Altera came up with a really nice way to handle multiple installed versions. Basically whenever you run the tool (Quartus) it will reset the environment variables accordingly for its use. Like I said, I can't remember if this was in place in 7.2. 

 Jake

[Altera_Forum]

Each installation is self contained. Ive quite happily run 6.1, 7.2, 8 and 9.0 all on the same machine.