Unknown 386 board

[Rainbow]

Recommended by Wim's BIOS...

[Rainbow]

I got a 386 board, of course with no manual. There's only one string printed on it "NC-C386CT V1.0".
It's full AT, has CHIPS chipset (one of the three chips has F82C351 on it, the two other have sticker over the marking), 6 16-bit ISA slots, two 8-bit and 16 (!) slots for 30-pin SIMMs (8 slots = BANK 0, 2 slots = BANK 1, 2 slots = BANK 2, 4 slots = BANK 3). There are also 8 28-pin sockets + three 24-pin for cache (there are two 22 pin chips "TOSHIBA TC55416P-20H" in two of the 24-pin sockets).
There's AMD Am386DX/DXL-33 CPU inserted in the socket and there's a free socket for math co-processor.
There are 16MHz and 80MHz oscillator soldered on the board and one oscillator is missing (there's free socket) - I think that 66MHz was there.

Does anyone know what miracle is this? I need the jumper settings...
I hope that I can get it to work at least to show some BIOS ID (AMI BIOS).

[edwin]

What size is full AT in centimeters?

any names near the front panel connectors? Any other jumpers on the board?

I'm going to have a go at it.

[edwin]

Number 1 suspect:

http://dainesn.tripod.com/th99/m/txt/31603.txt

[Rainbow]

The dimensions "330mm x 218mm" match the board, but the jumper do not.
The front panel connectors are as follows:
J1 SPEAKER
J2 KEYLOCK
J3 TURBO LED
J4 TURBO SW
J5 RESET
There's big red LED near the connectors which lights when the board is powered on.

Jumpers:
J23 DISPLAY (2-pin) near power connector (closed)
J25 INT. BATT (2-pin) (closed)
J24 EXT. BATT (4-pin) (connector)
Jumpers In the middle of board (near the F82C351 chip)
J20 (open), J19 (closed), J18 (closed) - all 2-pin
J17 (open), J16 (open), J15 (1~2) - all 3-pin
Jumper near two oscillators (I put 66MHz in the empty socket):
J6 (2-pin) (1~2) - selects between two oscillators (fixed 80MHz and the one in socket)
Jumpers near cache sockets:
J7, J8, J9 (all 3-pin, all 1~2)
J10 (2-pin, closed)
J11, J13, J14 (all 3-pin, all 2~3)
J12 (2-pin, open)

Seems that someone removed the cache.
The board runs, the BIOS ID is: "30-0200-ZZ0000-00101111-050591-PEAKDM_B", but it only runs at 8MHz.
There are many memory-related settings in the BIOS (more than one full screen).

BTW.: I have another one: same dimensions, same chipset, but different layout. Only "VER: 3.0", "MADE IN TAIWAN" and "3121" printed on the board, small sticker with "MSI:00008105". Solder points for 2x40-pin something under the 8 30-pin SIMM sockets. This one runs, but refuses to boot from floppy (haven't tried HDD).

I think that I will do a scan of both boards...

[Rainbow]

Scans are at http://rainbow.host.sk/myfiles/Unknown%20386/. I resized them to be smaller, but I have 300 dpi ones if you want.

[edwin]

I think the 3121 is an MS-3121 from MSI (Microstar). Get this file (zipped PDF with lots of settings):
http://www.ghks.de/ftp/pub/windows/driv ... jehpdf.zip

There are some pages about the 286 and 386 boards, it seems they had a more or less universal connector layout for the front panel.

Given the 80MHz crystal, the only thing I would trust in there is an AMD386DX40.



The other board is only shown half. You can dump the 300DPI scan for that one in my wimsbios email address, it's emptied daily.

[Rainbow]

Thanks for the file, but there's almost nothing about 386 boards

I tried the MS-3121 with the AMD 386DX/33 CPU (that came with the other board) - it worked fine in BIOS but refused to boot - floppy LED lights for a while, then stops (but num lock still works).
I alsto tried this CPU in PC Chips M321 - it runs at 40MHz fine here, boots into DOS without any problems and runs benchmarks fine (overclocked 386 )

[edwin]

No string shown at all?

[Rainbow]

I forgot to write down the BIOS ID string, but I remember that there was something like A137 displayed on the top of screen. I knew that I saw something like that before, but didn't knew where and what does it mean. Now I know - it's MSI BIOS version. (Axxx = AMI BIOS, Wxxx = Award BIOS). I wrote an e-mail to MSI tech support.
I will try both boards today - the turbo jumper on NC-C386CT and BIOS ID string on the MSI.

[ajzchips]

Try some luck here (only BIOS):
http://sky.net.ua/support/drivers.php?p ... OS%2F386DX

[edwin]

ROM3DX03.RAR

String:
30-0200-ZZ1256-00101111-050591-PEAKDM_B

Lucky Star board? Oh boy, it's already hard to find info about their '486 boards...

[Rainbow]

I tried the boards again. The NC-C386CT runs fine with jumper on the turbo connector (at 33 or 40MHz, depending on one jumper).

I removed the cache from the MS-3121 and set all jumpers below the cache to 2~3. This disabled the cache and board now boots without problems. Seems that the cache controller is bad. I put the cache to NC-C386CT (8 ATT chips) - there is no space for the 2 28-pin Toshibas (there are three 24-pin sockets with 2 22-pin Toshiba chips). The cache works fine.
I also tried the PC Chips M321 board with the cache - it runs OK too.
Here are some benchmark results (all boards with AMD Am386DX/DXL-33 CPU running at 40MHz - overclocked , Trident TVGA8900C 1MB ISA SVGA card, ISA HDD controller and 40MB Maxtor drive) from CheckIt:
NC-C386CT, default BIOS settings, no cache:
5816 Dhrystones
117.4K Whetstones
13546 CPS (BIOS video)
67932 CPS (Direct video)

NC-C386CT, tuned BIOS settings, no cache:
6765 Dhrystones
141.7K Whetstones
16255 CPS (BIOS video)
80748 CPS (Direct video)

NC-C386CT, tuned BIOS settings, 64KB cache:
11631 Dhrystones
204.7K Whetstones
25273 CPS (BIOS video)
131378 CPS (Direct video)

MSI MS-3121, default BIOS settings, no cache:
4911 Dhrystones
102.9K Whetstones
11407 CPS (BIOS video)
57678 CPS (Direct video)

MSI MS-3121, tuned BIOS settings (used AMISETUP), no cache:
6765 Dhrystones
141.7K Whetstones
16255 CPS (BIOS video)
80109 CPS (Direct video)

PC Chips M321, no cache:
4804 Dhrystones
102.0K Whetstones
12504 CPS (BIOS video)
58319 CPS (Direct video)

PC Chips M321, 64KB cache:
11049 Dhrystones
213.2K Whetstones
25273 CPS (BIOS video)
132660 CPS (Direct video)

[edwin]

So, tuning the bios gives about 50% performance increase

64kb cache doubles the performance compared to cacheless default settings.

interesting...