I have posted the following on a Thinkpad forum, but so far I haven't found a solution. I figured I might as well post here too since these 2 boards are the ones I know where I have a chance of finding people who may figure out what's going on.

I recently acquired a TP 755CX. It's actually my second one, and I also have a 755CE. I've installed a new HDD (it's actually a 1GB SSD in laptop IDE form factor) and installed Win98SE on it. The install went fine, except for the following.

The Mwave audio and modem functions were not detected during the install (Mwave is IBM's combination DSP/audio/modem card; it's essentially an embedded computer within a computer, with its own CPU and running an embedded OS https://en.wikipedia.org/wiki/IBM_Mwave ). There is no "unknown device" showing up in device manager, nor is there a modem or audio controller. I have installed the Mwave features package (v2.25a), which installs fine but still does not lead to the autodetection of the Mwave audio & modem. On the other 2 laptops (the previous 755CX and the 755CE) the Mwave would get detected and installed at this stage.

Now, I know that some 755CX machines didn't have a Mwave/DSP board. However, this one does have a DSP. If I go into setup (BIOS) I can test the DSP, and it tests fine. Also, I've installed the Thinkpad features disk (IBM's configuration utility for old Thinkpad laptops), and if I go to that and select DSP it does show me the DSP as installed and with the resources it uses (DSP enabled, I/O=4E30h, IRQ 10, DMA 7). However the next sections, the audio SoundBlaster compatible system and the modem system are greyed out and cannot be selected. The SoundBlaster emulation does not show any resources assigned, and the modem section although greyed does have some resources assigned, like port COM2 etc. The system has plenty of resources available, IRQ5 and 7 are free, DMA channels 0,1 and 2 are free etc so it's not an issue with insufficient resources.

I have also used the TP755 diagnostic disk to test the DSP/audio. On the initial screen it shows as: "audio card - connected (DSP card)"; then I went on to test DSP functions, and all pass. I can actually hear the sound the DSP generates during the tests through the laptop's speakers. But Windows still can't detect it.

Does anyone have any suggestions on how can I get this going? I don't really care about a functioning modem in this day and age (besides I have plenty of PCMCIA modems I could be using if I wanted one) but I want the sound to work for games.