The collected works of hermessgi

Just a guess.. :) It looks like you have your array connected to two different qla2342 controllers.. Try connecting both ports of the IR73 array to the same qla2342 controller..
Yes you can check the documentation. But I believe under display resolution it says "1024 × 768, 1280 × 1024, 1600 × 1024 (SGI Visual Workstation for Windows only), or 1600 × 1200 (Note: For 1600 × 1024, set the SI_SCREENRES environment variable to SI_1600X1024 for maximum horizontal display.)"
Looks like you can monkey with the environment script to make it work. I know I've set up a Dell 1920x1200 monitor and the SGI 1600x1024 monitor using the SI_SCREENRES environment variable.