This is an Asus P5E MB. It has always run XP Pro just fine. Upon upgrading to W7 Ultimate x64 the audio quit working. Device Manager says everything is fine but I uninstalled all devices and re-booted anyway. Upon re-boot W7 found and installed a driver it liked but still no audio. The devices shown in the control panel say nothing is plugged in even though both speakers and headphones have been tried. The "test" button where sounds can be verified is greyed out. I suspect this is a driver incompatibility however device manager says the best driver is installed. Any suggestions?