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Well, I've finally got all of the scoop on this particular issue. I actually got it from the people at Digispeech (makers of the Porta*Sound sound unit for laptops). Doom, and some others, write to the SoundBlaster registers directly with the processor in "protected" mode. Basically they are using a DOS extender (4GW) which allows them to use a full 32 bit address space. The IBM sound blaster emulation, and the Porta*Sound sound blaster emulation both rely on a feature of the '386 and above called "virtual mode". In this mode you can configure the processor to trap on I/O to individual addresses. Both IBM and Digispeech put an interrupt handler on this trap, and add the sound blaster I/O port (220H) to the list the processor should trap on. When an application "writes" to the SoundBlaster, the processor traps, the emulation code looks at what was written and then emulates the function. Since Doom and some of the newer Sierra Online games take the system out of virtual mode to run in, they disable this feature of the system and the emulation code CANNOT function. Basically this means you will never get the kind of sound the system is capable of out of the system with Doom because it doesn't have a register compatible version of the SoundBlaster hardware. (Note I expect it irriates IBM to no end that their otherwise WONDERFUL machine is screwed because they didn't follow the hardware _exactly_ of the defacto industry standard. Its ironic that the clone manufacturers already figured this out when they tried to sell MS-DOS computers that ran only "well behaved" applications of which where were about two.) Hence the newere version of the MWave chip that is SoundBlaster register compatible. Although a bit of hardware that decoded the I/O address and generated an interrupt would work too. So there is one light on the horizon but it isn't too bright at the moment. Windows (which like these DOS extenders runs in protected mode) has good support for audio and I've yet to find a Windows program that wanted audio that couldn't use the TP's chip. Microsoft is attempting to create a Windows/Games interface for fast interaction while preserving the device driver abstraction. Their *PROTOTYPE* customer is id software and DOOM. (there was an article on this in the San Jose Mercury News). If Microsoft is successful in defining a standard, and if the game writers use it, then all games from that point on will be able to use the TP750's sound. The risk of course is that no one has ever been able to create a "Games" OS that the games programmers didn't think "got in their way" so they went right to the hardware. --Chuck