I recently bought a Sony Laptop, model vgn-txn25n. It came with Windows Vista, but after several crashes, I decided to buy a copy of XP home and install it. The installation went fine, and the computer runs better than ever, but there is one problem: the sound. On the driver page provided by Sony (here it is: http://esupport.sony.com/US/perl/sw... , they say the driver is Realtek® High Definition Audio version 6.0.1.5350. I went to the realtek website, downloaded the comparable driver (that page is http://www.realtek.com.tw/downloads... for Windows XP, and installed it. I had sound. After restarting the computer twice, the sound stopped working. I reinstalled the driver, and I had sound again. I restarted the computer, and lost it again. The sound won't come back if you restart the computer again,or shut if off, and turn it back on, once it's gone, that's it. You have to reinstall the driver again. now, when I 'lost' the sound, the volume icon still appears in the taskbar (no, it's not muted :) ) and the device manager reports no problems with the sound driver. Can anyone think of a possible cause of this problem???

Don't know about that driver but I have had similar issues with drivers written for OSes prior to the one it was being used on. I have a realtek HD soundchip with six ports. My driver file doesn't match the version you posted. How many sound ports are on the computer? I think there is more than one realtek High definition sound chip.

Also, next time check the Device Manager to see if there is a problem with the driver. And go to the Control Panel > Sound and Audio Devices > Audio tab and make sure everything is OK there.