This motherboard is a cost optimized, late 386 platform which supports 486DLC processors.
You can find the jumper setting very easily with the search words "PcChips" and "M326" in the web.
One hint for the configuration: if you don't use a 387 co-processor (NPU) the jumper J5 must be set to 1-2 (NPU deactivated). It is not enough to disable the NPU search function in the BIOS only.
Performance
The chipset shows a inconsistent picture: a good cache throughput but a quite slow ISA-IDE speed.
I measured it with an AMD Am386DX-40 and a Cyrix Cx486DLC-40GP:
The BIOS offers only the clock speed as option for the ISA bus. I set it to "CPU-clock / 5" and checked it on pin 20 of the ISA slot: 8MHz which is correct.
I searched for configuration failures and I also tested different ISA-IDE controllers - without any success.
All measurement results are documented here.
Low ISA throughput
A simple cause could be: my board has a (hidden) malfunction. I don't have a second board but I own a 486 mainboard with the same SARC chipset (PcChips M601). The problem: we can't compare a 386 with a 486 motherboard but I have an idea...
In my cupboard are also the 367C (late 386 board) and the 4407 (typical 486 Vesa Local Bus board) from the manufacturer DataExpert. Both boards are also equipped with the same chipset: an UNIchip U4800-VLX.
Now I can compare the PcChips M326 with the DataExpert 367C for the 386 platform:
...and the PcChips M601 with the DataExpert 4407 for the 486 platform:
Finally the PcChips M601 has the same bad ISA-IDE performance as the M326. Perhaps the SARC chipset needs some delay or recovery cycles on the ISA bus...
Facts
| Manufacturer / Type: | PcChips M326 V5.2 |
| Year of manufacture: | February 1994 |
| Bios-String: | 40-0100-001437-00101111-080893-4386-H |
| Bios: | Version 5.2 |
| Chipset: | SARC RC4018A4 (02/1994) |
| SARC RC6206A4 (03/1994) | |
| Manual: | From stason with some corrections |
Summary
Strong points:
- Small board format but still five (16 bits) ISA sockets
- Support of 486DLC processors
- Processors with 33 and 40MHz possible (selectable with jumper)
Weak points:
- The SARC chipset has performance problems on the ISA bus
- Keyboard controller with socket (could be a height problem on two ISA slots)
falk.richter*at*yandex.com
Last update: May 22, 2021