It's still pretty interesting that there is a big performance gap between the 495SX and M1429 chipsets. They gap might also widen or narrow depending on the manufacturer of the motherboard, or which graphics cards are used.

Back in 2008/9 when I was doing my "testing", I didn't use Wolf3D for benchmarking. I remember in Windows I was using Wintune 2.0, but I can't recall what I used for DOS. But anyway, I can't think of too much software that will run on a 386 where the graphics will be the bottleneck rather than the CPU.

kixs wrote on 2022-04-03, 01:31:

I surely wouldn't call increase of 25+% minimal.

From what I remember that won't help you much unfortunately as this is just one benchmark and later games were all designed for at least 486. Only a fraction of them could be made playable by increasing AT bus frequency. Many games will be CPU bottlenecked or refuse to start due to usage of 486 instruction set. Games made for 386 do not require AT bus frequency increase and run fine at stock settings. I remember many 486 games were made for 486DX2 66 which is much faster than 386DX40. It's also pointless to run 386DX40 with VLB if the board accepts 486 CPU. It made sense only back in the day when the board was released.

There actually is a good reason to use VLB on a 386 if you have the option...you can place your linear frame buffer much higher in memory. Certain cards like the Mach64 ISA use what they call "aperture" to help with video acceleration in Windows. It sits just above 12MB. You need to disable the feature if more than 12MB of RAM is installed, which results in a sizable loss of performance.

Im still hoping for someone crazy enough to come up with a hacky 386 interposer wiring CPU data/address bus up to improvised VLB connector.

Anonymous Coward wrote on 2022-04-03, 01:46:

It's still pretty interesting that there is a big performance gap between the 495SX and M1429 chipsets. They gap might also widen or narrow depending on the manufacturer of the motherboard, or which graphics cards are used.

Back in 2008/9 when I was doing my "testing", I didn't use Wolf3D for benchmarking. I remember in Windows I was using Wintune 2.0, but I can't recall what I used for DOS. But anyway, I can't think of too much software that will run on a 386 where the graphics will be the bottleneck rather than the CPU.

I think 495 and M1429 chipsets have the same performance but Panda board has no option in BIOS to run the ISA bus faster, this is why the Panda is much slower with ISA VGA than 495. Actually with VLB the Panda is a bit faster than 495.

The Wolf3D benchmarking is new for me too. The official Wolf3D has no timedemo option. Wolf3D source code has been released to the public by id software (in 1995). Someone made this timedemo version. I have found it 1 or 2 year ago here in Vogons. I want to benchmark the 386 by a game, but Doom is too slow for a 386 this is why I have userd Wolf3D.

I agree, only few games will be playable on a 386 with VLB graphics card, which run too slow on a 386 with ISA VGA . (Actually the slowest DOS VLB cards like Matrox; Weitek Power 9000 and Avance Logic ALG2201 with 386 DX-40 are still too slow for Wolf3D.)

Gona wrote on 2022-04-03, 19:51:

I agree, only few games will be playable on a 386 with VLB graphics card, which run too slow on a 386 with ISA VGA . Might the Wolf 3D is the only one. (Actually the slowest DOS VLB cards like Weitek Power 9000 and Avance Logic ALG2201 with 386 DX-40 are still too slow for Wolf3d.)

Wolfenstein 3D runs fine on 386DX40 at standard ISA bus speed. I used to play it.

Transport Tycoon, Settlers 2 are 256 color SVGA games designed for 486 that benefit from faster bus.

I suspect all games rendering to ram buffer instead of directly to VGA memory will benefit greatly. FastDoom might be a good test.

Anonymous Coward wrote on 2022-04-03, 01:46:

It's still pretty interesting that there is a big performance gap between the 495SX and M1429 chipsets. They gap might also widen or narrow depending on the manufacturer of the motherboard, or which graphics cards are used.

I have some test results from OPTi 82C495SLC motherboard with Am386DX-40 (+ Cyrix CX-83D87-40-GP FASMATH). This is the only VLB mobo that I have that supports 386, but I always had pretty good opinion of the ALI chipsets (good RAM performance).

Trident TVGA8900D (1024k x32):
* TOPBENCH:
91
* Speedsys 4.78 VESA mem:
4201 kB/s
* 3DBench (1.0, 1.0c):
15.8, 15.8
* PC Player Benchmark (320, 640):
3.7, 1.5
* Landmark 6.00:
69 MHz AT, 144 MHz 80287, 3810.23 chr/ms
* Doom (low, high):
2134/2836, 2134/11393
* Chris's 3D Benchmark (320, 640):
13.7 (8.2 fps), 4.3 (2.5 fps)

Cirrus CL-GD5424 (VLB):
* TOPBENCH:
113
* Speedsys 4.78 VESA mem:
8922 kB/s
* 3DBench (1.0, 1.0c):
18.1, 18.1
* PC Player Benchmark (320, 640):
3.8, 1.6
* Landmark 6.00:
69 MHz AT, 144 MHz 80287, 9102.22 chr/ms
* Doom (low, high):
2134/2620, 2134/9558
* Chris's 3D Benchmark (320, 640):
14.7 (8.8 fps), 4.8 (2.8 fps)

ISA speed was set close to 8MHz, no overclocking, the point was to compare systems and cards, not to get the best results the mobo is capable of. That being said I had the best memory and cache timings set that I considered stable. As you can see there isn't that much difference in actual performance except raw memory speed, which means you'll get most gains in games that use SVGA modes, especially if there's a lot of screen redraw each frame. Doom at low settings is pretty much CPU bound completly. I can tell Transport Tycoon runs a bit smoother with VLB card. In other words - VLB VGAs are sort of wasted on 386 but on the other hand, if you have such a card, and VLB capable mobo, it will work and provide some performance uplift. It might also be cheaper than hunting for the fastest pure ISA cards out there.

Also keep in mind the 8900D I'm comparing against is no slouch either when equipped with 1MiB of VRAM, it can then do 32-bit memory transfers internally and that make it some 20% faster than C and CL models of 8900 and 9000 series. And it has 0WS jumper as well. Might not be the fastest ISA VGA but certainly is a good match for a cached 386DX.

Nice stuff.

Here's my thoughts about your bench mark results.

These tests nicely show the additional video bandwidth, but possibly reflects on the quality of the video BIOS coding too. Pretty sure you must have video rom shadowing turned on.

1             Speedsys 4.78  Landmark 6.00 
2Card            VESA mem      Video
3TVGA8900D ISA  4201 kB/s    3810.23 chr/ms
4CL-GD5424 VLB  8922 kB/s    9102.22 chr/ms
5Percent Gain    112%           139%

The lack of improvement in these benchmarks suggests that there significant CPU & Memory resistance flinging pixels because we don't see the same proportional gain on the VLB card moving to the more demanding video modes.

1                Chris's 3D      Chris's 3D      PC Player      PC Player    
2Card           Benchmark 320   Benchmark 640  Benchmark 320   Benchmark 640  Doom (low)  Doom (high)
3TVGA8900D ISA  13.7 (8.2 fps)  4.3 (2.5 fps)    3.7            1.5            26.3 fps    6.6 fps
4CL-GD5424 VLB  14.7 (8.8 fps)  4.8 (2.8 fps)    3.8            1.6            28.5 fps    7.8 fps
5Percent Gain    7.2%            11.6%           2.7%           6.7%           8.2%        19.1%

I don't know enough about TOPBENCH to say much about this.

1Card           TOPBENCH
2TVGA8900D ISA     91
3CL-GD5424 VLB    113
4Percent Gain    24.2%

Deunan wrote on 2022-04-04, 14:21:

Trident TVGA8900D (1024k x32):
* Speedsys 4.78 VESA mem:
4201 kB/s

It would be great if you could re-run Speedsys benchmark with 13Mhz ISA bus and Trident TVGA8900D. It should provide about 50% performance uplift for video transfers. That is significant for 256 color SVGA as it needs to transfer 4x more data than VGA.

AlexZ wrote on 2022-04-03, 20:41:

Wolfenstein 3D runs fine on 386DX40 at standard ISA bus speed. I used to play it.

True. On a 386 DX-40 with overclocked ISA bus, most late ISA VGA cards enough for Wolf3D.

AlexZ wrote on 2022-04-03, 20:41:

Transport Tycoon, Settlers 2 are 256 color SVGA games designed for 486 that benefit from faster bus.

I have tested Transport Tycoon in Panda and 386 DX-40 with the fastest DOS VLB graphics card ARK1000VL. It is playable (with SB Pro sound and music too).

Gona wrote on 2022-04-04, 18:15:

True. On a 386 DX-40 with overclocked ISA bus, most late ISA VGA cards enough for Wolf3D.

it's also fast enough on normal bus speeds, I recently played through all of Wolfenstein 3D, extra levels and Spear of Destiny... about 40-50 hours or so on my 386DX-40 with ET4000AX 😉 it runs perfectly fine.

imi wrote on 2022-04-04, 19:31:

Gona wrote on 2022-04-04, 18:15:

True. On a 386 DX-40 with overclocked ISA bus, most late ISA VGA cards enough for Wolf3D.

it's also fast enough on normal bus speeds, I recently played through all of Wolfenstein 3D, extra levels and Spear of Destiny... about 40-50 hours or so on my 386DX-40 with ET4000AX 😉 it runs perfectly fine.

Wow! 😁

No idea how I used to play Wolf3D on a 286-16 with PC beeper back then 🤣