This is a zip file of the driver needed for the Compaq Presario 4540 Onboard Sound (ESS 1887). I had tried downloading this from Driverguide as well as from Compaq and ESS Technology and none of them worked. I finally found this zip file on another Presario 4540 in which the sound card worked. I transferred the file to my ailing 4540 and it works perfectly now. I have only tested this for Windows 95, but I think it will likely work with Windows 98 as well.