Fastest FPS possible for 386 CPU on High Detail?

[holygamer]

Could you please tell me what the max FPS is that you can get with a 386 CPU on High Detail mode.

I this the best possible setup?:

• Am386DX-40
• 8 MB RAM
• Fast ISA VGA card (Tseng ET4000AX, Trident 8900C, or Cirrus Logic GD542x)
• AMD 387DX-40 FPU
• L2 256KB Cache (8x 32KB SRAM + 1x 8KB TAG)
• Windows, FastDoom and Doom installed on CF Card

Am I correct in that adding more RAM won't make a difference since the CPU is a bottleneck?

Does FastDoom use the FPU?

What's the fastest possible FPS in High Detail mode that I can get with a 486 CPU?

Will Doom II player created WADs work since Doom II works?

Thanks

[viti95]

Is this the best possible setup?

Technically, the fastest 386 ever made was the IBM DLC3 (also known as BL3), which runs at 100 MHz. However, these CPUs are extremely rare. There are also a few 386-compatible motherboards with VESA Local Bus support, but those are also very hard to find. If you're limited to ISA bus, the best video cards are the Cirrus Logic GD-542x series and the OTI 087X.

It's also possible to use a real SSD with a SATA-to-IDE adapter and an XT-IDE BIOS. In my experience, these setups are slightly better than CF cards and significantly more reliable, although they might be a bit overkill for most use cases.

Am I correct in that adding more RAM won't make a difference since the CPU is a bottleneck?

Adding more RAM helps prevent slowdowns. The more RAM you have, the more WAD data can be cached, reducing the need to read from the hard drive.

Does FastDoom use the FPU?

No, FastDoom doesn't use the FPU. The FPU is too slow on 386 and 486 CPUs, and it's not possible to parallelize FPU and CPU instructions on these architectures. It's more efficient to perform all calculations on the CPU.

What's the fastest possible FPS in High Detail mode that I can get with a 486 CPU?

A fast 486, such as the Am5x86-P75, can reach around 70 FPS depending on the scene and with a fast video card, if you enable the unlocked framerate option. Otherwise, it runs at a stable 35 FPS.

Will Doom II player created WADs work since Doom II works?

They should work fine, although I haven't tested many user-made WADs extensively.

[holygamer]

Thanks for the info. So with the best 386 CPU that's not rare to find and the other best parts mentioned before what's the fastest FPS I could get with High Detail mode?

With a 386 what's the max RAM that's FastDoom can use?. I thought after a certain amount of RAM the CPU can't use any more as the CPU is a bottleneck?

On a 386 or 486 PC what's the cheapest way to get the music to play using the Roland SC-55 soundfont with FastDoom?

[viti95]

Not much, around 10 to 12 FPS with everything set to High Detail. A 386DX just isn’t fast enough to run DOOM smoothly at full detail.

FastDoom doesn’t have a specific limit on how much RAM it can use (technically the limit is around 2 GB), but beyond a certain point it doesn’t make much difference. For example, the DOOM II WAD is about 14 MB, so having 16 to 24 MB of RAM is beneficial, as it allows the entire WAD to be cached in memory.

As for SC-55 music playback, the cheapest option is to use a MIDI-to-USB or RS232-to-USB cable and connect the system to a "modern" PC running Nuked-SC55 (an SC-55 emulator).

[holygamer]

What I meant was I wanted to get the music for Doom on FastDoom to sound like it's played on a Roland SC-55 such as emulation like what GZDoom can do. Or is there a device such as a Rasperry Pie or other single board comuter device which I can add to a 386 or 486 PC which will emulate the music of Doom on FastDoom to sound like it's being played on a Roland SC-55?