This company is a bit like Sun Microsystems, you can hear a note of awe in the voice of those who knew it at its peak. This was a bit before Ciro Santilli's awakening.
Those people created OpenGL for God's sake! Venerable.
Both of them and Sun kind of died in the same way, unable to move from the workstation to the personal computer fast enough, and just got killed by the scale of competitors who did, notably Nvidia for graphics cards.
Some/all Nintendo 64 games were developed on it, e.g. it is well known that this was the case for Super Mario 64.
Also they were a big UNIX vendor, which is another kudos to the company.
Video 1. Silicon Graphics Promo (1987) Source. Highlights that this was one of the first widely available options for professional engineers/designers to do real-time 3D rendering for their designs. Presumably before it, you had to do use scripting to CPU render and do any changes incrementally by modifying the script.