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Am386DX/DXL not posting

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First post, by Neolyum

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Hi! 😀
I am trying to build a build with a Am386DX/DXL and an old Morse 80386 M3 Motherboard I found in a box which was an old PC of my parents.
On it is a 1MB Memory Module and I bought a Trident TVGA-8900D-R graphics card.
As all of these parts are 5 years older than I am, I don't have any experience with these kind of parts and I need help and it seems, this is the right place to ask, so hi, here I am 😁

I connected an ATX power adapter with an ATX to AT adapter and I think I connected the both parts correctly (black adjacent to black). What got me wondering, on the board is a Chip, labeled as "Am386DX/DXL-33" but I don't know what that one is, as a PGA socket is on the board labeled "80386" so I thought, *that* was for the CPU. Because the board refused to boot without anything in that socket, I bought two am386dx/dxl-33 and inserted them. Here is problem 1: what is the right direction for them? Did I do it correctly?
With these CPUs inserted, there was little difference - no beeps, no video. So I looked for some documentation for the motherboard and found some jumper configuration and set monitor mode to colour and Batterytype to intern as I don't think I have an extern one.
(is it ok to post links here?)
Because I had no jumpers for the first times, I used a fork (shame on me), and while connecting the jumper for colour video (leaving external battery jumper open) it beeped 3 times ^-^ meaning base 64k memory error? Are the "modern" beep codes correct for these old boards?
After that I installed jumpers in the same configuration as with the fork, but I didn't get any response after that 🙁

Problem 2: The big capacitor next to the external battery jumper seems to be corrodated, would that stop the board from booting? How could I clean it?

The CPU(s?) gets warm, the PowerLED Pins work, the turbo switch and its LED do work too, so something IS working here 😁
There was no difference with the second CPU I have, but I don't have the possibility to test any of the parts 😒

Does anyone has some ideas for me? 😀

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Reply 1 of 90, by Horun

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Yes you have the PGA 386DX cpu inserted correctly but should not need it as it has a 386DX soldered on board. You need to remove that blue barrel battery and pull the BIOS chip and clean that area with vinegar then ISO alc.
Post another closeup picture of the battery area after cleaning.

Hate posting a reply and have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. 🤣 Second computer a 286 12Mhz with real IDE drive ! After that came 386, 486, Pentium, P.Pro and everything after....

Reply 2 of 90, by Neolyum

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Horun wrote on 2020-12-12, 17:50:

Post another closeup picture of the battery area after cleaning.

Will do so, thanks!
When there is a soldered 386 on the board, why does it have a PGA sockel available? Dual CPU wasn't possible at that time iirc 😁
And is it a problem having the cpu inserted?

Reply 3 of 90, by Horun

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The PGA is for upgrade if the soldered CPU is a 25 or 33Mhz, no it will not hurt to have it installed.
Be sure to use 4 matched SIMMS in sim5, 6, 7 and 8, I see you only have one installed in the picture in sim1.
http://www.win3x.org/uh19/motherboard/show/3844

Hate posting a reply and have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. 🤣 Second computer a 286 12Mhz with real IDE drive ! After that came 386, 486, Pentium, P.Pro and everything after....

Reply 4 of 90, by Neolyum

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My ISO alc just arrived and I tried to clean it as best as I can. The blue cap is glued onto the board, so I could not remove it, but I cleaned the Keyboard BIOS socket.

I only have this one RAM stick, will it post without the others? or at least beep so I know it's alive 😁
If I buy some, what do I have to pay attention to?

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Reply 5 of 90, by Neolyum

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After the board was dry again, I tried to start it. The first time, it beeped one time, but no image.
After many tries with no reaction, I had one where the board beeped 3 times, pause, 3 beeps and so on, but never an image. Is the problem the missing 3 SIMMs?

And another question, if I insert the "upgrade" CPU, both become quite hot, without, the soldered 386 stays handwarm - is this expected?

Reply 6 of 90, by debs3759

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That big blue cylinder isn't a capacitor, it's a battery, and as it has leaked it needs replacing (or at least removing, but then it won't save CMOS settings) yesterday, before it does more damage. You should also carefully check nearby tracks on the board, as battery acid can damage them. I can't see any corrosion, but if there is any, it will potentially stop it working, or at least affect performance until fixed.

See my graphics card database at www.gpuzoo.com
Constantly being worked on. Feel free to message me with any corrections or details of cards you would like me to research and add.

Reply 7 of 90, by Neolyum

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debs3759 wrote on 2020-12-15, 17:47:

That big blue cylinder isn't a capacitor, it's a battery, and as it has leaked it needs replacing (or at least removing, but then it won't save CMOS settings) yesterday, before it does more damage.

I removed it, now I get these 3 beeps everytime ^-^ I think this is a good sign. Does it mean, that my SIMM is broken or does it need the full stack of 4 to post?

Reply 8 of 90, by debs3759

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I think it needs a full bank of 4 identical (or identical spec) simms, but I can't claim to be an expert as I never tested it myself.

See my graphics card database at www.gpuzoo.com
Constantly being worked on. Feel free to message me with any corrections or details of cards you would like me to research and add.

Reply 9 of 90, by debs3759

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Is it one long and two short beeps? If it is, it's a memory error (although at least one site suggests video error). If three short beeps, as far as I can tell it is likely a RAM error, so could be because of only having one simm

See my graphics card database at www.gpuzoo.com
Constantly being worked on. Feel free to message me with any corrections or details of cards you would like me to research and add.

Reply 10 of 90, by Neolyum

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debs3759 wrote on 2020-12-15, 18:31:

Is it one long and two short beeps? If it is, it's a memory error (although at least one site suggests video error). If three short beeps, as far as I can tell it is likely a RAM error, so could be because of only having one simm

it's 3 beeps with the same length, I'd say it is rather long, but I don't know any codes which are 3 long 😁

If I buy SIMMs, how do I know they are compatible? Is there something else than latency? I am thinking of those two sets:

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Reply 11 of 90, by debs3759

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It's OK for the two banks to be different, as long as each bank is recognised.

I found https://www.gigabyte.com/Support/FAQ/816 which says 3 short beeps is "basic memory 64K address check error"

See my graphics card database at www.gpuzoo.com
Constantly being worked on. Feel free to message me with any corrections or details of cards you would like me to research and add.

Reply 12 of 90, by Deksor

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A 386 DX can't POST with just one SIMM.

if you look here https://www.computerhope.com/beep.htm#ami, you can see that 3 beep code means "Base 64 K RAM failure." That's pretty much a RAM related issue and it makes sense since the computer can't POST with just one RAM stick.

The reason is simple : these 30 pin simms have a 8 bit data bus. But the 386DX has a 32 bit data bus, so you need 4x 8 bits to get 32 bits, so four memory module.

A 286 or a 386SX needs only two and if any 8088 have had 30 pin simms, it'd need just one.

By the way, can you shoot a photo of your motherboard without any expansion card inserted and with a good lighting/angle so we can add it to UH19 ? (and if you get it running, send us a BIOS dump from your board ; I'll give you instructions on how to do that, it's pretty easy). Here are some examples : http://www.win3x.org/uh19/motherboard/show/2134

Edit : well debs3759 was quicker ^^
About the latency, 60ns is plenty for a 386. I've seen 386s runing with 80ns simms without any problems and most 30 pin simms are 70ns iirc (lower is better).

Trying to identify old hardware ? Visit Ultimate Hardware 2019 - Project's thread The Ultimate Hardware 2019 (UH19) project- a stason.org/TH99
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Reply 13 of 90, by pentiumspeed

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386 is 32 bit datapath and needs 4 30 pin modules to make one bank. 30 pin modules are 8 bits wide while 72 pin module (on other boards is one module at 32 bits.).

Cheers,

Great Northern aka Canada.

Reply 14 of 90, by Neolyum

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Good to know, thanks!
Is this image ok? 😀

And it does seem that my soldered 386 is broken, without the PGA one I get no reaction from the board xD

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Reply 15 of 90, by Deksor

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Yes it's pretty good ! I've added it to the page 😀

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Reply 16 of 90, by Horun

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Neolyum wrote on 2020-12-15, 19:40:

Good to know, thanks!
Is this image ok? 😀

And it does seem that my soldered 386 is broken, without the PGA one I get no reaction from the board xD

That is odd but not uncommon. What else is odd is there is no jumper to change from PQFP (soldered) to PGA (socketed).
Have a few 386 with soldered + socket and they all have a jumper to tell chipset which CPU.
Unless that is what S1 jumper (not in the documented layout but is on your board) is for but is not near the cpus' where it should be if that is what it does.

Hate posting a reply and have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. 🤣 Second computer a 286 12Mhz with real IDE drive ! After that came 386, 486, Pentium, P.Pro and everything after....

Reply 17 of 90, by Neolyum

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Horun wrote on 2020-12-16, 03:27:

Unless that is what S1 jumper (not in the documented layout but is on your board) is for but is not near the cpus' where it should be if that is what it does.

Should I try to close it? Or should I wait until my memory arrives to test that?

Reply 18 of 90, by Robin4

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Neolyum wrote on 2020-12-15, 17:37:

After the board was dry again, I tried to start it. The first time, it beeped one time, but no image.
After many tries with no reaction, I had one where the board beeped 3 times, pause, 3 beeps and so on, but never an image. Is the problem the missing 3 SIMMs?

And another question, if I insert the "upgrade" CPU, both become quite hot, without, the soldered 386 stays handwarm - is this expected?

386SX = You need 2 installed as 1 complete set

386DX = You need to install 4 simms as 1 complete set..

Best what you can do is buying a complete set of 4 modules (1mb each for 4MB) 8 simms for 8MB.

All the simms needs to be at the same speed.. So if one is 70Nano Second. then the rest need it also be the same.

~ At least it can do black and white~

Reply 19 of 90, by Mvickers03

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Sounds like you will get this running with a full bank, you don't seem to have cleaned up the leakage enough.

That battery will continue to damage things until you remove it, The acid literally emanates from the battery until it's removed.