I found the reason why FIFA 98 RTWC and FIFA 99 was crashing with dynamic_x86 core: The sound emulation. By pure luck, when the game crashed this time, I was sent back to the desktop, I tried to restart FIFA 98 RTWC, and I was told it could not enable Sound Blaster Card (ingame). I tried to set up a match and I was finally able to play (although without any sound). Then I quit the game and tried FIFA 99, also no sound, I was able to get past the kick off for the match.
Probably with dynamic_x86 core, the cycles were the problem (I tried 60000, max, 100%, no luck for sound). I think the sound with dynamic core is unable to keep up with the "graphics speed" somehow.
I tried to use Glide High level emulation, I put the files almeath sent me on /usr/local include and lib folders, changed my dosbox conf to glide = true, apparently DOSBox-X log says he is able to use OpenGL to emulate voodoo, but I saw no noticeable speed difference. All these tests were done when both games failed to initialize sound hence why I was able to get past the kick-off for match.
With dynamic core and no sound, FIFA 98 RTWC and FIFA 99 were quite similar to VMware Fusion speeds when using my Windows XP virtual machine there. I think XP was faster and smoother, but DOSBox-X had a great improvement on dynamic core versus normal core for these games. I think we now need to find out what was the problem with the sound that caused the game crashes before kick-off moment.
Also, I was forced to play in windowed mode.
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