1) The most important thing for getting the engine running fast is the 3d-accelerator, so you gotta decide if you want to create this engine for 1st, 2nd or 3rd generation hardware accelerators.
2) I own an Elsa Victory Erazor (Riva 128, 4 MB) and my engine works pretty fast on a 233 mmx. I use Direct3D Immediate Mode, but it renders about 4000 Polygons per frame with a relatively high frame-rate (with 17 different textures). So in RM, you can easily use up to 2000 polys per frame.
3) Create your engine that it'll work with older cards, too, for example drop down the screen resolution or bit-depth to make it running faster. I've got problems with page-flipping with my card, I dunno why, so I checked the caps before and then decided between using page-flipping or blitting.
CU
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Skullpture Entertainment
#40842461