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First post, by Great Hierophant

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The most important piece of hardware you need to run DosBox is a fast CPU, the faster the better. There are certain Dos games run in DoxBox that could bring even the mighty Athlon FX 55 to its knees, today's fastest gamng processor. (I won't even consider running a version of Windows and trying to play a game.)

This makes sense. In the old days, even a 486DX2 was not fast enough for some of the last Dos games. You really could get up to a Pentium 200 before you could stop. But aren't there ways to reduce the emulation overhead? For example, for systems with an x86 processor, why not let it handle the instructions while DosBox simply sends it to the processors at a speed that the game expects. Cache and compensate, superscalar architectures and branch prediction can be eliminated by sending the instructions to the processor abnormally slower.

What about the graphics and sound cards in a computer these days? A user with a processor like the Athlon 64 isn't going to cripple it with second-rate GPUs and APUs. Does DosBox use the Geforces, Radeons and Audigys for more than glorified frame and sound buffers? If these cards can take some of the heavy burdens off the CPU, then by all means use them and let the CPU concentrate on processing logic, not pixels or waveforms.

Reply 1 of 2, by HunterZ

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The reason DOSBox doesn't pass instructions directly to the host CPU is not so much a speed issue as that DOSBox is intended to be cross-platform. They didn't want to waste time making and supporting optimizations that were only meaningful to a portion of the supported platforms (i.e. x86).

For graphics and sound, I'm not sure how much they take advantage of things. I can tell you that the SDL is used, so any limitations that it imposes are limiting DOSBox. I would hope that they're using multiple hardware DirectSound buffers for mixing each emulated device (and each voice on the Gravis Ultrasound) when possible, but I have no idea. For video I know that SDL has some shortcomings (such as not using real hardware overlay on my ATI card), and DOSBox probably has a few on top of those. It's also worth reiterating that Win32 or x86 or any other platform-specific optimizations to video and sound emulation will probably not be officially implemented due to DOSBox's cross-platform nature.

Reply 2 of 2, by `Moe`

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Well, today is my "search the forums" answering day, so please search the forums 😉 This has been discussed sooo many times.

The short result is: Yes, x86 CPUs already do some work natively (that's dynamic core), no, most soundcards can't help dosbox (except for MIDI wavetable synthesizers and real MT32's - those are supported), and yes, the GPU could theoretically help dosbox, but not in a performance-increasing way - look at my OpenGL-HQ patch to see how your GPU can make games look better, but not run faster.

And before answering, really, please search the forums 😉