Also had a DX4-75 in a laptop a ways back, AST Ascentia, that one never felt very snappy either. Probably slower than DX2-66 machines, think I tried Duke3D and had to make the window real small. Doom was better, but actually playing it, it did a 1, 2, 3 FREEZE repeat.. freeze was quarter or half second, but sooooooooo annoying.

Edit: I get dizzy when we teleport in from another thread like that 🤣

Many thanks for insights, but I would like to see some real world tests, benchmarks comparsions of DX4-75 vs DX2-66. I know, they should be "similiar", it's basicaly similiar case as Pentium 75 and 66, which were benchmarked at many various places already.

I suspect in synthetics and number crunching, DX4-75 would be faster, but in anything with quick moving graphics or text, the DX2-66 would dominate. It is the degree of dominance that you are after. I don't have numbers, but my guess would be 10%. If you indicate exactly which applications you are interested in, there is a higher probability that someone will come along and run the tests.

feipoa wrote on 2021-12-02, 00:32:

I suspect in synthetics and number crunching, DX4-75 would be faster, but in anything with quick moving graphics or text, the DX2-66 would dominate. It is the degree of dominance that you are after. I don't have numbers, but my guess would be 10%. If you indicate exactly which applications you are interested in, there is a higher probability that someone will come along and run the tests.

Doom and Wolfeinstein 3D for games, maybe PC player benchmark, and some of those standard tests for software under DOS, they test mostly ALU, FPU, cache speeds, in some units. MDK DOS benchmark is not bad choice too. (or Quake 1 for FPU-intensive comparsion)

Talking laptops though you're somewhat to very screwed by the implementation and can do little about it. If I was stuck with a DX4-75 CPU on a half decent desktop board, I'd be trying it at 100 right away, with a reasonable sink on, and if it didn't like that, try the 2x multi by board setting or socket trick and try dx2-80.

It's pretty certain it would come out over dx2-66 on synthetic tests because icomp index is higher. We've seen that DX50=DX2-66 myth thrown out though, as no benchmarks seemed to support the anecdotal data that held it as "snappier" or more responsive. On same boards with same cards it'll fall in line, but there's probably a 20% margin between best of one and crappiest of another system.