I've tried both options but without success, unfortunately. I'm getting no sound or signs of life on an oscilloscope, except for the voltage coming from the Dallas battery. I'm guessing I should give up on this board. Unless I can somehow verify the BIOS chip? (I do have a chip programmer)

That makes sense. I will try it out (hopefully later today) and report back.

Thanks for the replies :) You need 1 and 3. pretty sure that's wrong - speaker data is referenced to positive voltage so he would need 1 and 4 I've tried connecting a normal PC speaker and didn't get any sound. Of course this could mean the board is just dead, but that's when I found out this …

I have an Vtech M486-UPI motherboard ( manual ) that seems to be dead, as it's not POSTing or anything. I'm hoping it is doing anything at all and that's it's broadcasting an error beep. But the speaker connector is (for me, at least) strange: it has *three* of the four pins that need to be …

Ah, but it's not muted for me. And running ESSVOL after going to DOS from Windows has no effect. Which drivers do you use? The ones found on Vogonsdrivers?

Thanks! That works but not always. When I boot into Windows, I cannot get any audible MIDI in DOS even after a soft reboot (Ctrl-alt-del or Windows "restart" option). Only a hard reset or powering the system off and booting directly to DOS gives me music, if I add the '/a' parameter to ESSVOL. I'm …

I have a ESS 1869F ISA card that used to work well in DOS, until I installed drivers for it in Windows 95. Since then MIDI music in DOS has disappeared, even though programs like DOSMID and games reports no problems in playing MIDI files. Judging by this topic from 2017 I'm not the only one …