Can you post Doom benchmark scores? From phils dos benchmark?

Warlord wrote:

Can you post Doom benchmark scores? From phils dos benchmark?

will try it this weekend and post the results 😀

Here you go:

https://www.youtube.com/watch?v=JEohcb3IqwU

Thanks for making the effort.

Interesting results from your Doom test:
low-detail + small screen: 38.5 fps
high-detail + full screen: 9.4 fps

Figured i should share some of my 386 metrics:
PC-Chips M321, tightest bios timings, 45MHz: ~35 fps and ~9.3 fps, respectively.
FX-3000, tightest system timings, 45MHz: 34 fps and 8.8 fps.
FX-3000, tightest system timings, 50MHz: 38.6 fps and 9.8 fps. <- no FPU, comments below.
FX-3000 runs at 55MHz as well, but the relaxed system timings make it slower than the 50MHz setup.
Asus 386/33-64k running at 50MHz: 36.5 fps and 9.5 fps (there are no settings in the bios, but i can tell the default wait states are high and the bus clock divider is at least 4).

Excluding DLC and other hybrid hardware:
FPUs are a major limiting factor for 386 system speed.
So far i haven't seen a system with FPU that runs reliably (3d rendering grade) at 50MHz or higher. For this to work, timings have to be significantly relaxed which results in performance equal or lower than 45MHz with tightest timings.
33MHz rated FasMath FPUs cannot go over 45MHz. 40MHz rated FPUs can operate at 50MHz but with relaxed timings, which wipes out any performance advantage from the higher clock speed.

From my experience 45MHz seems to be the sweet spot for fully maxed out system with 32Gb RAM, 256Kb SRAM, FPU.
50-55MHz seems to be the practical limit with some compromises.

Your Doom beast is one of the best around !

I tend to agree with pshipkov. For the most part, 45MHz is going to be a fast as you can go on most 386 boards without sacrificing stability, however, some later 386 boards that use 486 chipsets designed to tolerate 50MHz can work at that speed reliably. I haven't tested all of my 386 boards extensively, but I was able to get my 486SXL2-50 working on a 50MHz FSB on an OPTi 495SX board and it seemed pretty solid. However, I did not stress test the FPU, and it's entirely possible there could be issues there.

pshipkov, which FPUs did you test at 50MHz? I have late production code 40MHz chips from IIT, ULSI a Cyrix, as well as a few 33MHz Intels, and special ones like IIT X2 and ULSI Math-Co DX2.

Agreed.

It will be great if you list some of the better late 386 mobos that you encountered over the years.

As for 387 FPUs - i am more interested in "clean" systems, meaning no DLCs and other hybrid hardware, so don't have much experience with them. Sorry.

I test with IITs, ULSIs, i387, Cyrix FasMaths - the usual suspects.
As i mentioned above:
The 40MHz rated ones are ok-ish at 50MHz.
The 33MHz rated ones are fine at 45MHz.
The fastest of them (clock-to-clock) is a 33MHz rated all-gray Cyrix FasMath, but sadly - it is a no go for 50MHz system.

Very curious about Weitek Abacus 3167. Apparently it was a top dog in the 386 class. Many major 3DCCs at the time supported it. Never got one ...

If one considers 386 hardware upgrades and late hybrid 386/486 mobos - wonder if the RapidCAD CPU/FPU will actually be a good OC candidate ? Even that Intel's HW back then didn't overclock very well, it is basically a 486 class silicon, which should be able to climb higher than the 386'es.

Outside of CAD, I don't think a 3167 would be very useful...even less than a i387.
There are grey top Cyrix 83D87s with the old markings rated for 40MHz. I presume these must use the older core, but are probably pretty rare. Who knows if it would overclock any better than a 33MHz part either.

To be honest, there aren't a lot of great late 387 boards, because by that time they were all in budget systems, and almost exclusively use 486 chipsets. I like 386 boards that use true 386 chipsets, and therefore I like the SiS Rabbit, VLSI Topcat, and in theory the C&T PEAK/DM should have been amazing but half of the advertised features don't seem to work as far as I can tell.

I only have two later 386 boards. One is a brandless OPTi 495SX board, which isn't too bad, and a Biostar board I haven't played with much yet, but it uses a rather obscure chipset...I think it's by FTDI. It's a pretty late one, so I have high hopes for it.

I want JOJO, I want JOJO (JOJO, JOJO)!!!

Now is the time for your next project... about Blood y tal.

@Anonymous Coward.

But back in the day FPUs mattered pretty much exclusivelly to CADs and 3DCCs anyway. There was not much else out there that needed them - some spreadsheets maybe and obscure science apps perhaps. 😀

Thanks for the rest of the info.

@ rayante

Looking forward to his next "infernal device" ...