I don't see too much being posted about Wdmex.

Could be that the procedure to success is clear, in the instructions. Also, it is pretty clear that it might just not work, even if you've done everything right.

Mostly, for some reason or another, Wdmex has nudged drivers "that are for my system (Win98FE)" to actually work. Some drivers, at the edge of dropping Win98 support, were not very good.

Recently, I tested a 2009 Win2K-Vista Sigmatel C-major driver. Fortunately, the driver still used the "Chicago" signature. The .inf file modifications were minor. Entries like "something.nt.inst" just needed converting to "something.inst".  There where no registry entries or folder locations, that needed WinNT to Win9x conversions.

The .inf file was too big for Windows 98 to use. I don't know what the size limit is. But I was able to fix that, by deleting localization info I didn't need. Also, the file was in unicode text format. It needed to be saved as a plain text file.

I haven't extensively tested the driver. I did notice, that when selecting options for mixer controls, that the record (line-in/mic) options where located in playback; this rather than the record category. I don't know if that will cause issues with some programs, when trying to assign input.

Also, the head phones now have their own mixer bar, rather then just automatically being controlled by the main volume. However, the main volume still determines the final output, once you un-mute the head phones and adjust that volume. I'm guessing that this setup is common to newer versions of Windows. The main volume control only adjusts the speakers.

The previous drivers, generic Realtek Vxd and Wdm, were limited by directsound emulation. The new drivers are not listed as such, and test fine under Dxdiag. I've had other issues, with the Realtek drivers, and haven't test against them.

The AC97 Sigmatel is a pretty cheap audio device. So even though this is a success, in means of quality audio production (recording/sampling), I haven't accomplished much. But I could see non-emulated directsound being useful.

Rloew, where ever you are (in the beyond), thanks again!

Edited October 14, 2025Oct 14 by awkduck

INF file size limit for Win9x is 64KB I'm pretty sure.

Are you sure these drivers did not work without WDMEX? Do you get sound?

I hope you're not talking about HD Audio, that would be a major breakthrough  

8 hours ago, MrMateczko said:

I hope you're not talking about HD Audio, that would be a major breakthrough

I wish I was talking about HD Audio. There is sound. But yeah, it worked without WDMEX.

So, I revisited this machine (with a fresh install) and WDMEX is needed to get the audio working. Once the driver is established as functional, it seems I can disable WDMEX. If I swap the driver out, and then back again, WDMEX is once again needed to initiate functionality.