The Difference between
IRIX Versions

 General Information


Currently the newest version of IRIX is 6.5.18 which supports most modern SGI computers is of course the best choice in many cases. But there are two cases where you might consider using older versions of IRIX: You have an old SGI that isn't supported by IRIX 6.5 any more or you have a supported SGI which is too slow or has less than 128MB of memory. This page tries to explain, which version of IRIX fits best to your needs.

The IRIX Versions

IRIX 4.0


IRIX 5.3


IRIX 6.2


IRIX 6.3


IRIX 6.4


IRIX 6.5

This is the newest stream and runs on most SGI hardware. Supported are all current hardware, all legacy systems with R4000 CPU or better except Crimson.


Personally I would recommend the following versions for these machines:

Machine Recommended IRIX Version
Personal Iris IRIX 4.0.x
Indigo R3000 IRIX 4.0.x or
IRIX 5.3 for machines with at least 32MB
Indigo R4000 IRIX 5.3
Indy IRIX 5.3 for machines with less than 128MB
IRIX 6.5 for machines with at least 128MB
Indigo² IRIX 6.5 (should have 128MB)
Octane IRIX 6.5
O2 IRIX 6.5 (should have 128MB)

You might also try to install IRIX 6.5 on supported machines with less than 128MB of RAM, but you might want to downgrade to IRIX 5.3 for better performance.