lo siento por otras palabras,,,espanol negativa.
www.driverguide.com free signup required if these don't work: username "drivers", password "all".
Once signed in, click on "sound card" icon, next page choose y for manufacturer, then Yamaha from list and hit "select manufacturer", then at Yamaha page type in ymf724. Do not add the G because the one post for that is a file that won't work. You'll get a spread sheet of listings. Then go to the top of that page to refine search, choose win98 from "os", choose "all drivers" from date box, hit the bar for search. You'll get another spread sheet, 56 entries. Choose of with multiple ymf listings that includes ymf724 and is 6.1mb download, as well as 100% under comments.
Download and put into a folder you make as "Yamaha".
Double click it and it should unzip the files into that folder or it will designate where it's putting the folder. Remember this because it's where you'll have to choose the PC to look for those drivers.
THEN GO TO device manager and simply remove all the YAMAHA devices, NOT the modem wave devices.
RESTART your PC and it will come along to either reinstall the Yamaha drivers or prompt you for the drivers. I suspect it will and is why I'm suggesting you download the drivers, as many newer video and sound devices don't nicely put the files listed in the INF file so you can reuse them, as it calls for a xxx.vx_ instead of vxd for example.
all this hassle to reinstall the Yamaha so it will reassociate and work right. If it doesn't, the onboard sound may have blown and you'll need a add-in sound card.