Installed my newly purchased EVGA 770 Classified 4GB last night, but have lost my onboard sound. I tried turning of HD Nvidia sound in the device manager and reinstalling my realtek audio drivers. I have an Asus M5A97 LE R2.0 MB that is running UEFI BIOS and cant for the life of me find out how to change the audio settings. Help please?

This, sadly, did not fix my issue. :(

Try doing a system restore back to a date when the sound was working without issue. 

Sounds like a driver conflict. Here is what I would do...
 
#1 Download & Install CCleaner & Driver Sweeper 3.2.0.
 
#2 Remove all NVIDIA & Realtek software from add/remove programs.
 
#3 Reboot info safe mode & Create a restore point.
 
#4  Run driver sweeper 3.2.0, check mark NVIDIA - Display, NVIDIA - PhysX & Realtek - Sound, select Analyse button, if a list of entries pop up select the Clean button, when asked to reboot select Cancel. Do the scan again to make sure all entries are removed/deleted, if all entries cannot be removed/deleted please post that the entries cannot be removed/deleted along with a screenshot showing what cannot be deleted. If the entries were removed/deleted successfully continue onto the next step...
 
#5  Run ccleaner, select the registry tab, select scan for issues button, select fix selected issues button, when asked to backup the registry select "no" (we made a restore point earlier, we don't need to worry about backing up the registry entries.), select fix all selected issues button. Do the scan again to make sure all entries are removed/deleted.
NOTE: Two entries may still appear after multiple cleanings (it should be one or two and no more), this is normal and should be ignored, all other entries should be gone. 
 
#6 Reboot into normal windows mode.
 
#7 Perform a clean installation of video drivers.

1. Uninstall Precision X/Afterburner, make sure to select "no" to saving profiles when asked. Reboot the machine.
2. Download & save 337.88 driver to your desktop. 
3. Double click on 337.88-desktop-win8-win7-winvista-64bit-english-whql.exe located on your desktop & run the extractor.
4. Select custom advanced install, under custom installation options uncheck all options but graphics driver & physx system software, if you are using audio over HDMI please select the HD Audio driver, if you have a 3D capable monitor and would like to use 3D at some point select the 3D Vision driver also, check mark perform clean install, then click next to install the driver, reboot when asked.
5. Re-install Precision X/Afterburner, do not install both choose one or the other.

 
#8 Download & Install the latest realtek drivers from here.
 
Hopefully it works now. 

What is connecting the video card to the monitor? DVI? Display port? HDMI? Have you tried different speakers or headphones?

You may want to verify that the audio device that you are not using is disabled in the windows device manager as well, then reset the computer.

EVGATech_BrittonT
You may want to verify that the audio device that you are not using is disabled in the windows device manager as well, then reset the computer.

Verified and reset.
 

EVGATech_Erik
Try this .  Might need to do one more install of the drivers after doing this.  Do also make sure that your speakers are set to the default device under playback devices.

Followed it to the letter. Again with the same results. Could it have tripped something up in the BIOS? I have this stupid UEFI bios that I cant make anything out of.

Sounds like just a simple setting being overlooked.
 
Need to have the onboard HD audio enabled and configured in BIOS..BIOS -> Advanced tab -> Onboard Devices Configuration -> SB HD Azalia Configuration -> Enabled
 
Need to have the audio playback device (speakers/headphones) set as default as mentioned above.
 
May need to make a configuration change in the Realtek HD Audio Control Panel for output to speakers/headphones.

I'm no audio guru by anybody's standards, but I would try uninstalling the Realtek HD Audio Driver through Control Panel -> Programs and Features and reinstall it and configure again..Restart your PC after uninstall/reinstall..Get the driver from Asus here.
 
Maybe there's a setting in the NVIDIA Control Panel -> Display -> Set up digital audio that needs changed..Other than that, hmmmm.   

I have tried that. I even went so far as to disable the NVidia ones in the device manager. I have now also tried to uninstall all NVidia drivers, and still no audio.

Same thing as the new card. No audio when I re-install the old card now either.

OK then it should be a software issue. However, when you installed the new card it is entirely possible you could have nudged or bumped an audio cable slightly out of place so check that carefully and reseat any audio cables in that area. 
 
Should that fail then a complete fresh install of Windows might be needed if you did not make any type of backup. 

I checked all of my cables. Everything seems snug.
 
No, I have not tried HDMI or display port as my monitor only has DVI input.

Ok I uninstalled all audio drivers, and can now get audio through hdmi to my tv, but I am still unable to get it to play through the onboard audio/speakers.

chrisdglong

rjohnson11
OK then it should be a software issue. However, when you installed the new card it is entirely possible you could have nudged or bumped an audio cable slightly out of place so check that carefully and reseat any audio cables in that area. 
 
Should that fail then a complete fresh install of Windows might be needed if you did not make any type of backup. 

This solution is a thing of the past. I have NOT had to reinstall Windows because of issues like this since XP. 

You're correct and you shouldn't have to. This is a last resort tactic if nothing else works.