Hi There i have the same problem, i have a eMachines - E4034 with motherboard
http://www.e4allupgraders.info/dir1/.../msi7173.shtml
(MSI MS-7173 (RC410M) Mainboard)
i have tried eMachines main website, but no luck. i even asked one of the tech people, but they sent me to the website of where the board info is on, but i still have no luck with sound nor SM Bus controller, Multimedia controller appears as sound i prosume as thats the only thing, that and SM Bus Controller with a question mark in Device manager
Any help would greatly be apprecated
thanks
Wizkid005