Are you looking for Dell’s OptiPlex GX280 audio drivers that are compatible Windows 7? After 5 minutes of research on www.dell.com, I was fortunate to find the following 32-bit Windows 7 audio driver (R145551) which I installed and tested on one machine then used it’s cloned hard drive for the remainder of computers I had to upgrade to save valuable time.
Analog Devices ADI 198x Integrated Audio
Release Date: 1/24/2007
Version: A25 5.12.01.7010
Download Type: Driver
File Format: Hard-Drive
File Size: 3MB
If you do not have the ability to clone hard drives as I do, you will want to burn the audio driver to a CD or DVD with other useful files you will need for your upgrade or any available USB Flash drive. Please keep in mind that these USB Flash drives are prone in getting viruses so use caution.