A few little updates, as this 286 evolves yet again.

Board now at 16mb or ram and running stable (so far...), tried several different sticks now I have gone through and sorted my parts collection, not checked what they are like at 30Mhz and unlikely to do so now that I have DRAM chips in doing EMS. Looking at memory usage of the EMS side, 320K available from 704K. Need to read up more on how the chipset/ software does this.

Now I know why the DC-200 was probably at the back of my card collection, cannot be sure but think/ kind of remember that it is not compatible with CD-ROM and similar type drives (i.e. tape) and testing seems to reflect this at the moment.

So, need a way to connect the CD-ROM up, first throught was the sound card but that does not have an IDE connector, so back to all the bits I found in the tidy up and one was an ESS1868F card with IDE Connector, now it took me a while to find a sound card that would work in this motherboard last time which was a concern, and well it worked first time, a bit of mucking around to get the CD-ROM driver to work but again stable, even the original DOS drivers work also header for the wavetable so should have good MIDI.

One little bonus is my DC-200 seems to be fully up to date with the latest BIOS and firmware and able to do LBA!

So future plans now:

1) BIOS update/ tweak/ reverse engineer. Thought I had a Mr. BIOS image for this chipset but I do not, but there is a few newer versions out there and might be able to engineer to have more options open to me.
2) If I am going to push the board it will not be up to 30Mhz maybe something a little more modest if I can find the crystals.
3) Still not happy with the video card, but it will do for the time being...

I may not be able to build a super fast 286 but now she is stable I am more than happy at them moment, now it seems to be running stable and the fact I keep being distracted playing games! But maybe I can create a very capable 286.

EDIT:

While going through my collection, I cam accross a ATI 8514 Ultra so the MODEM has been taken out and the original ET4000 (needs RAMDAC replacing) has been put back in as it had a feature connector (which the ET4000/W32 card does not), so the build is now:

1Mb ET4000
1Mb ATI 8514 Ultra

ESS Audio Drive (with wave table and supporting CD-ROM)
3COM Etherlink III
SIIG Serial Pro card (of course LPT as well)
Promise DC-200 (with 16mb installed and LBA BIOS)

Hopefully that will be it for the build (for a while anyway), so for future things:

Need to do some benchmarks next.

Did anyone ever test out the older ATI Mach8 drivers I uploaded last year?
According to my user manual they should work on a 286.

Anonymous Coward wrote on 2022-08-10, 14:42:

Did anyone ever test out the older ATI Mach8 drivers I uploaded last year?
According to my user manual they should work on a 286.

No, not seem them. However, I had some disks already (v2.41 I think), the Windows 3.1 drivers work straight away with this machine, and DOS drivers seem to work as well.

Seem to remember that the later drivers only worked on a 386 and above and also stripped support for the crystal fonts, to me the later drivers were worse.

The drivers I uploaded are version 1.3. If you have any need for them, you can find them attached to this thread:
Should a Diamond Speedstar Pro (CL-GD5426) work in Win3.1 in 286 real-mode?

Anonymous Coward wrote on 2022-08-10, 23:57:

The drivers I uploaded are version 1.3. If you have any need for them, you can find them attached to this thread:
Should a Diamond Speedstar Pro (CL-GD5426) work in Win3.1 in 286 real-mode?

Will give them a try, but drivers I have work a dream, using WinTune 2.0 as it was the only benchmark tool (for Windows 3.1) I had at hand:
640 x 480 standard Windows 3.1 VGA driver on left and 8514/A Ultra score on the right:

Throughput: 537 1115 Kpixel/sec
Open window: 0.038 0.066 sec
Text scroll: 3.12 0.922 sec
Live/ Curve draw: 40.042 8.932 sec
Fill: 5.892 missing sec (oops)
Colour Fill: 3.957 2.336 sec
Close window: 0.595 0.49 sec

I know it is not a fair test using the standard VGA driver, but still shows the difference, apart from opening windows and the fill result I lost! I will do another benchmark at some point, but a nice boost to a 286 running Windows 3.1

The DC-200 with cache I did not expect to do much (if anything) as it is attached to a CF card, but with all options off (no cache no bios) results are using WinTune 2 again:

219 Kb/Sec (weighed)
298 Kb/Sec (uncached)
141 Kb/Sec (cached)

With everything on (Tubo BIOS/ Turbo Cache)

598 Kb/Sec
774 Kb/Sec
422 Kb/Sec

Tried all the settings step by step and as you turn on the different BIOS modes and cache modes, you do see an increase each time, still not ground breaking results though, in fact very poor results, I was using a slower CF Card though, but still very poor results, more adjustments needed there. However, WinTune is expecting SmartDrive and complains about not seeing it, so could be in-accurate results because of that.

Now I tried the LBA function on the DC-200 and it does work. However, after I put a large CF Card in (8Gb) and turned on LBA mode, booted from floppy and was able to partition and format it would, DOS reads it correctly through the BIOS, but after that it would not boot, so thought it might be a MBR thing and it was. So simple, what you have to do after partitioning and format is to use the FDISK /MBR (DOS 6.22) option and it will boot the large drive. So I currently have a 2Gb CF card running in the build now, plenty of games now!

This begs the question, how the hell did I use Office and Windows 3.1 on a 286-12 all those years ago! Without all these nice add ons, I can only imagine I had plenty of tea breaks between loads!

Update time, system is stable (or as can be expected with the experiments being tried out)! Windows 3.1 working well, DOS working well (as expected a ton of games played!), a few issues with MIDI using the new ESS card (expect this is a driver issue), but thought I would turn my attention to something else, that being OS/2! An OS I looked at in magazines in the 90's with envy and still use on one of my systems.

My main knowledge with OS/2 is Warp 4, so did not expect 1.x to be too much of an issue, boy, how I was wrong. Went for a direct install of OS/2 using the install disks and HPFS, but it failed everytime using a 512mb CF Card, which is annoying as it worked before. However, there has been a lot of hardware changes, what did work is this:

Dropped to a 256Mb card, installed a DOS/ FAT partition first (went for PC-DOS just to keep it semi-IBM) and it works! Might try and push it to 512 again, using the PC-DOS/ FAT method.

The system may not look pretty, but is the solid worker I expect out of a 286, a few little niggles here and there still but no major complaints

Nothing much going on at the moment, changed the RAMDAC on the ET4000 and majority of the issues have gone (i.e. snow at top during certain graphics transitions), found a ADV476KN80E which is odd as I thought these only went up to a 66MHz clock rate not 80MHz, but took a risk as it was a couple of pounds and it seems to do the job.

Had a look around for a datasheet, but just confirms my memory that they only made 35, 50 and 66 MHz verions.
Anyone else seen these 80MHz versions?

Wouldn't be the first time a datasheet simply wasn't updated when a higher speed rating was released. Digikey has a listing for your Analog ADV476KN80E so I would be inclined to believe it is a genuine article indeed.

The highest resolution that I've ever found occasion to use on a 286 (1024 x 768 @ 60 Hz) has a pixel clock of 65MHz, so even a 66MHz rated part should be perfectly adequate.

BEST OF LUCK TO YOU

I also want to restore my late father's 1st ever computer IBM ET&T PC-XT that he gifted me.
Hope you will be kind enough to guide and support me to restore his loving memory.

ayandon wrote on 2022-09-01, 03:36:

BEST OF LUCK TO YOU

I also want to restore my late father's 1st ever computer IBM ET&T PC-XT that he gifted me.
Hope you will be kind enough to guide and support me to restore his loving memory.

Hello and welcome!

Been a while, so have been playing with the BIOS on the motherboard, got a copy of a 386SX HT18C as far as I can tell latest version of the BIOS (more options to play with in the setup looking through the binary), burnt a chip put it in and well nothing! Which is a little odd I thought.

So I have a collection of BIOS chips for testing and none of them work with this motherboard, typically I can at least get a POST out of all of them on other motherboards before they error out but nothing at all with this.

So pulled back the label on the original BIOS chip and it is a M5L27512K-2 (200ns) pin compatibile to the M27C512-10 (100ns) chips I am using, would the difference in speed make that much difference?

Also anyone know where to find wolf_286.exe anymore? Cannot find it anywhere.

Not updated this for a while, been in the process of getting a new job which has paused a few of my projects. The machine is quite happy running, got an CF card for DOS, Windows 3.1 and OS/2.

OS/2 is a pain though, even if I have it formated to FAT certain files get damaged i.e. COUNTRY.SYS if I put the CF card in another machine, in particular Windows 11. I do not know what it keeps doing, but certain operating systems are broken if I put the CF card in my Windows 11 machine for file transfers, OS/2 in particular but also I have an NT3.51 build and that will just be not usable if I put it in Windows 11, which is mad as they are both NTFS, different versions but still, Linux plays nicely though.

Anyway just thinking where to take this build next, might play around with CAD next as I have the 8514/A and numeric processor in there.