I cleaned inside my PC today (used compressed air). I plugged it back in and now my sound card isn't being detected? I go to my sound playback and ASUS Xonar isn't even listed. And the software that comes with it isn't running either, even when I try to start it manually. I already took out my computer again, touched the card and shit but It still doesn't work. Wtf is going on. It's a ASUS Xonar DG 5.1.
Download and reinstall your sound card drivers.
Check bios and make sure it didn't lose track of the card when you pulled it out and switched over to onboard sound. Reset it to you sound card if necessary.