OK, I have Voodoo3 too and my CPU is 1200,
Glide64 - Best (the author of glide64 has Voodoo3) fast and nice
Jabo D3D 1.5 - Fast and OK with 90% of the games, very rear minor errors
TR64 Opengl 0.8.1 - Good Quality but little slow.
TR64 D3D 0.5 - Fast , quality is not very good.
Unofficial Daedalus 0.7b - Works OK but not good gfx quality
If you want try this Opengl plugins that support only 32depth buffer you can try WickedGL 3.02 by MetaByte , but the screen flickers all the time.