Some time ago, I found this:

This is the steps to run an Octane[,2] with both an ODYSSEY and an IMPACTSR framebuffer. This is a totally unsupported configuration but it seems to work. It took a little bit to get it working, beacause OpenGL and thus MPlayer, Quake3, etc. only work on the IMPACTSR driven monitor (we want it to be the ODYSSEY driven one). For this, we have to relink libGL.so and libGLcore.so in:

/var/arch/lib
/var/arch/lib32
/var/arch/lib64

To the ones present in:

/usr/gfx/arch/IP30ODSY
/usr/gfx/arch/IP30ODSY32
/usr/gfx/arch/IP30ODSY64

respectively. After that we didn't even need a reboot and everything just worked. It would seem that the only drawback is that we can't have OpenGL on both screens, but that's fine, we can use the other one for gaim, firefox, etc. We CAN also run at different refresh rates across the two monitors too, so don't worry about that.

To get it running from scratch install the XiO card load IRIX from or boot into the miniroot and do:

keep *
install fresh

This will add the additional drivers we need for the extra card. After it reboots do the fix described above. Additionally, you can do:

chkconfig -f xinerama on

to enable xinerama (desktop spanned across both monitors) which also seems to work great. =====

But I tried it, and there are two problems:

• The Inst tool just installs the drivers of the card(s) in the machine. Or at least, that's how it works with IRIX 6.5.29 medias.
• When started with the two cards, the Octane switches display on the ImpactSR board.

So… It's absolutely not tested… to me, there are two solutions to make this happen:

• Either install the machine from scratch with the two cards installed, with the display on the SI/SE.
• Or, if you have an IRIX installation with the VPro drivers already functioning, boot the machine on serial console (without keyboard/mouse), and try to install the missing Mardi Gras drivers.