Literally, JJ2 does use your graphics card, but only for features that are common in any 'modern' system.

I've got one Toshiba notebook from 1995 that still works, with a 486DX on 75Mhz and 24MB RAM. This is the only system I have that doesn't run JJ2 very well. It misses 'MMX support' and 16-bit colors, and still runs on an awful framerate. Even turning the light effects off does only improve framerate by 5 to 10. Honestly, using Plus actually breaks it because it appears to use more memory than the original JJ2 code. But I'm talking about an ancient system here with 24MB of memory..