4 ms·
Even if the CPU was fast enough to do all the graphics work, getting those pixels to the framebuffer could be a bottleneck. See benchmarks on p287 of the same a
by andrewf 5y ago
Even if the CPU was fast enough to do all the graphics work, getting those pixels to the framebuffer could be a bottleneck. See benchmarks on p287 of the same authors' Doom book at https://fabiensanglard.net/gebbdoom.pdf https://fabiensanglard.net/gebbdoom.pdf (https://fabiensanglard.net/gebbdoom/ https://fabiensanglard.net/gebbdoom/ if you'd like to pay for it):
A 33Mhz 486 ran Doom at 7, 11, and 15 fps respectively on three graphics cards.
A 66MHz 486 ran Doom at 8, 13, and 24 fps respectively on the same three cards.
The cards would've been attached with the same bus: 8-bit AT bus at ~10MHz, 16-bit AT bus, and 33MHz VESA local bus. (The 66MHz CPU is "clock doubled" so same equivalence for accessing memory, cache beyond L1, etc).
tl;dr if you had an older graphics card in your PC, it would be the bottleneck and having the CPU run faster may not have helped.