i want a audio driver for optiplex gx520 for windows 7 ultimae 64 bit
Try this one, it's for vista x64, so it should pass for W7.: http://ftp.us.dell.com/audio/R145149.exe
(This package provides the Analog Devices ADI 198x Integrated Audio Driver and is supported on Optiplex GX280/GX520/GX620/SX280 ).