Hey Folks, long time lurker needs a bit help with the above board I got from eBay. I'm very comfortable with old tech, having a 286 when I was 11 and then 386/486/P1/PII/P3/etc. In fact I've stayed current and am also building a new AM5 rig for present day gaming.

I'm using a Am5x86-P75 CPU with this board, I've got all the jumpers correctly assigned and even got a little overclock to 160Mhz from it (active cooling with thermal paste).

I initially had problems with the board hanging with the cursor flashing after the 378 address for the parallel port: (pic from the net)

So I ripped out the SRAM cache and disabled it in the bios and now it gets past that and polls the floppy disk drive to boot (new 1mb cache ICs coming)

But, here's what I can't get past:

With MS-DOS Disk 1 in the drive it still comes back with boot failure, or I/O error. I've tried 3 different floppy drives, umpteen 34pin cables but to no avail. The floppy drive seeks at POST and comes on to read the disk after post but it just wont boot from it. I've even tried an ISA controller with a floppy port (disabling the onboard controller in the bios) but the same thing happens. I've tried different RAM combinations and even disabled both IDE controllers.

Inspection of the board reveals no damaged traces, its in really good condition.

This is a pic of the board I purchased from ebay:

Which I believe is this one:

https://www.elhvb.com/webhq/models/486pci/r418v2.html
and
https://theretroweb.com/motherboards/s/m-tech … 8-pci-486-ver.2

I see in the manual there's some settings for setting the DMA but I dont have JP36 or JP37 on my board:

DMA Channel JP36 JP37
-----------------------------
1 2-3 2-3
3 1-2 1-2

I'm thinking it could be a BIOS issue, looks like this board and either run with an AMI or Award BIOS but I'll need to get a flasher before I attempt this (never done that before). BIOS loads with Award Rev: Kw (latest that I can see)

Has anyone faced a similar issue? I'm really at a loss here 🙁