32-bit Z-buffer and memory questions

[rickn]

32bit Z will make objects in the distance clearer, but it comes with a small perf hit. For games like quake2 I would not use 32bit Z.

As for 32mb, you will see a difference in games like Quake 3 when using large textures at 1024x768 32bit.

An image at 1024x768 32bbp, and triple buffering uses 12.5mb alone for the frame buffer, so that leaves 3.5mb of memory for textures. You end up doing alot of AGP texturing, which of course in a game like quake3 will cut your frames down significantly. For most current games though 16MB cards are sufficient for 1024 gaming.

[Gareth Randall]

32-bit Z-buffer and memory questions

Thanks to the advice of you guys, I've got Quake II running under OpenGL on my G400 16Mb - and I understand what all the fuss over 3D gaming is about! =;-)

Got a couple more questions, though; it seems that the default setting for 32-bit Z-buffering is "off". I tried turning it on and running QII, and it crashed mightily just after the opening screen. Does 32-bit Z-buffering make that much difference to the image quality?

Second, what kind of difference would I see with a 32Mb G400 over my 16Mb? Would all games run faster with more detail at all resolutions, or is the primary advantage that it would allow me to run at insanely high resolutions (currently I use 1024x768x32, QII screams along and my 15-inch monitor won't go much higher anyway)?