Both boards appear to have shortcomings. The top board is interesting because it uses a Forex chipset I've never seen before on a 386 board...single chip. That could be a pretty fast chipset. Unfortunately, the board only has 4 SIMM slots and only up to 128kb L2 cache.
The lower board has many sockets for cache RAM, but unfortunately it only supports the lower density 8kx8 chips, which means a maximum of 128kb. Based on the design of the cache, it's possible that it only accepts 1MB SIMMs too. You won't know until you try.
Why would a motherboard manufacturer design a board requiring so many DIP cache modules? Is this cache density configuration a requirement of the chipset?
Plan your life wisely, you'll be dead before you know it.
This post will be a bit off topic... but still on topic.
I found a dead ISA only OPTI 493 486 motherboard
The corrosion damage. (I'm not the one who has scratched the board)
A Shuttle HOT-403 with a boring AMI BIOS dated the 6th of June 1991 and a non working motherboard with a MR BIOS... This is an opportunity to see if the MR BIOS brings any profit.
Here is a picture showing the two motherboards side by side. Most of the stuff match except for the OPTI F82C206 integrated peripherals controller (where the CMOS lives) versus the UMC UM82C206L. These chips are both copys of the Chips 82C206 from the NEAT AT 286 chipset so any BIOS that works with one should work with the other. Notice the HOT-401s serial number 91-00321. 😀
Well was the MR BIOS still alive? ... yes 😀
Did it bring any profits? Not much but I could now choose at what rate the memory is beeing refreshed and that did bring a minor improvement.
Above: AMI. Below: MR BIOS. The CPU is a vanilla 486 DX2/66.
I will upload both the 386 and 486 OPTI 391/493 MR BIOS images later. Perhaps they are one and the same, who knows.
Edit
Corrected some faulty information
/Edit
Last edited by Skyscraper on 2018-03-05, 18:26. Edited 2 times in total.
New PC: i9 12900K @5GHz all cores @1.2v. MSI PRO Z690-A. 32GB DDR4 3600 CL14. 3070Ti.
Old PC: Dual Xeon X5690@4.6GHz, EVGA SR-2, 48GB DDR3R@2000MHz, Intel X25-M. GTX 980ti.
Older PC: K6-3+ 400@600MHz, PC-Chips M577, 256MB SDRAM, AWE64, Voodoo Banshee.
Could you provide the cachechk v7 memory read and write results? Is your DRAM wait state set to 0 in MR BIOS? Could you provide a screenshot of the MR BIOS chipset, cache, and memory settings?
Using MR BIOS made a fairly generous enhancement on my UMC 481/482 based board. If I recall, the ram read timing went from something like 11 MB/s to 14 MB/s, or about a 30% increase.
Plan your life wisely, you'll be dead before you know it.
Could you provide the cachechk v7 memory read and write results? Is your DRAM wait state set to 0 in MR BIOS? Could you provide a screenshot of the MR BIOS chipset, cache, and memory settings?
Using MR BIOS made a fairly generous enhancement on my UMC 481/482 based board. If I recall, the ram read timing went from something like 11 MB/s to 14 MB/s, or about a 30% increase.
I will add a HDD later, then I wll run all sorts of benchmarks. 😀
The AMI BIOS for the HOT-403 actually defaults to 0 wait states while the MR BIOS defaults to 0 read 1 write wait states if I remember correctly.
Both the Speedsys results used 0 wait states and pretty much identical settings.
Hidden refresh and slow resfresh were disabled in the AMI BIOS as the HOT-403 didn't like these settings with 8x4MB memory or at least not the "hidden refresh", I don't remember if I tried the "slow refresh" setting by its own. If that setting works I think the MR BIOS loses its performance advantage.
The MR BIOS also had hidden refresh disabled but instead of a "slow refresh" setting it had actual values and the refresh was set to the slowest setting, probably 60us or something like that.
I will post more "screen shots" of the MR BIOS when I get home, I'm at work at the moment.
Last edited by Skyscraper on 2018-02-23, 07:04. Edited 3 times in total.
New PC: i9 12900K @5GHz all cores @1.2v. MSI PRO Z690-A. 32GB DDR4 3600 CL14. 3070Ti.
Old PC: Dual Xeon X5690@4.6GHz, EVGA SR-2, 48GB DDR3R@2000MHz, Intel X25-M. GTX 980ti.
Older PC: K6-3+ 400@600MHz, PC-Chips M577, 256MB SDRAM, AWE64, Voodoo Banshee.
Here are the requested pictures showing more of the OPTI 493 MR BIOS (486) setup.
These are the default settings (I'm running without a battery and I'm too lazy to change anything except for the HDD and floppy settings if I'm not benching).
This is the OPTI 493 MR BIOS from the 486 board. The dump was made with NSSI. Don't try this BIOS if you don't have a way to recover your old BIOS if it dosn't work.
Looks similar to the MR BIOS for my UMC 481/482. Yours has a refresh method, which is nice, and an option to set the refresh cycle period. Mine does not and I have to use a DRAM program for DOS to set the refresh period. I find 40 uS is about right. 15 us is typically the default if it is not specified or if there is no option for "slow" or "hidden" refresh.
Plan your life wisely, you'll be dead before you know it.
What about PC Chips M326 V5? I found one with integrated AMD 386DX 40mhz. Chipset is CHIP11 9426-ACS / CHIP13, soldered 20ns 128kb cache apparently. Worth a buy?
I must be some kind of standard: the anonymous gangbanger of the 21st century.
I suppose if you want to restrict your CPU to that of an AMD 386DX and 128 KB cache and the brand doesn't bother you, it might work for your needs/desires. Such a board woulnd't interest me in the least. I wouldn't even accept it for zero cost with free shipping - not worth the loss of storage space.
Plan your life wisely, you'll be dead before you know it.
Cache doesn't matter that much after 128k, judging by popular opinion here. Also this board have space for socket, but it's not soldered. Looks similiar to that one, minus CPU socket, board color (green) and few PCB changes to fit soldered CPU: http://www.amoretro.de/wp-content/uploads/pc- … motherboard.jpg
I must be some kind of standard: the anonymous gangbanger of the 21st century.
Depending on the revision of your AMD 386DX, you can completely disable the CPU by setting the FLT# pin to ground. Luckily, the FLT# is next to a GND pin, and you can desolder the FLT# pin and bend it over such that it is touching the GND pin. Turn on your soldering iron and reflow the solder of the GND. Once you float the AMD 386DX, you can solder on a PGA-132 socket and run any CPU. You may not have to do the FLT# to GND solder procedure if your motherboard has a jumper to float the onboard CPU.
It is my personal preference that I like to run 256 K on my PGA-132-containing motherboards and 1024K on my socket3-containing motherboards.
Plan your life wisely, you'll be dead before you know it.