The audio chip IS different in the 755 CE Note well the 'E' after the C. I guess E stands for Enhanced. And it _is_ compatible with Doom. There is also a 755C (note there is no E) and it uses the same audio chip as the 750C and it is NOT compatible with doom. The buzzword is "the MWAVE Chip" which is only available on the CE, CsE, and CD models. --Chuck