After a happenstantial exchange with
@treellama on IRC I agreed to purchase a 4MB SGRAM module for the LPX-40/Tanzania/4400/StarMax etc etc motherboard, and it arrived in good time! Booted right up in my StarMax 5000.
It allows the onboard Rage II+ DVD chipset to support 24-bit color at up to 1152x870, 16-bit up to... somewhere, but I have no monitor to test that anymore.
Feels maybe a touch snappier, but that might be some sort of cognitive/observational bias placebo or whatever. I decided to run MacBench's complete graphics suite of tests, and the results were interesting. The baseline is the standard, on-board video with 2MB or EDO VRAM, and I also compared the results from a PCI Rage128 video card.
Since it's an aggregate, it's very interesting to see that the Rage128 is only 70 points ahead of the on-board SGRAM score.
Here's a patch of test scores that favor the on-board (vs the Rage128 only because apparently I run inconsistent tests…):
And here's a patch of test scores that favor the Rage128:
And these just have my head scratching a bit…