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Games that benefited from having a NEC V20?

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Reply 20 of 21, by mothergoose729

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Scali wrote:
mothergoose729 wrote:

Beyond that though, the speed in certain DOS games definitely feel a bit too fast, even at 4.077mhz. This compared to running the same game in DOSBox at 315 cycles, which is what is recommended for a 4.77mhz 8088.

DOSBox isn't exactly very accurate. 315 cycles is just a ballpark figure, but how it actually compares to a real 8088 depends on the instruction mix used by the game.
In DOSBox, all instructions are equally fast. On a real 8088, there are huge differences in execution speed between instructions.

That's true. They "feel" to fast, but I would need to try them on a real 8088 to know if that is a problem with the CPU or a just a problem with the game.

Reply 21 of 21, by VileR

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Yep, and there's also the rest of the machine to consider - memory, video wait states, etc.. PCjr also uses a 4.77Mhz 8088, but the system design (chiefly the video/RAM architecture) makes it effectively much slower than a PC or XT. As a result, games adjust for this and in DOSBox some of them need ~150-170 cycles to run as intended.

(Edit:) from memory, at least a few of those problematic games are BASIC jobs... maybe it's an interpreter compatibility thing?

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