HELP! New Video card killed my sound!

So I recently upgraded my video card from an 'ASUS 9600GSO TOP' to an 'ASUS EAH4850'. The video card is the ONLY thing that's changed in the computer, and now I only get audio from my left speaker! I've never had any issues with this PC before, and everything was working great before I made the switch. As a note, I'm running Altec Lansing 2-ways + self powered sub. The sound is output to the sub, then rerouted to the speakers themselves. The left one is the only one that works, but the volume, bass and treble control are mounted on the right speaker, and they work fine. Because of this, I can only assume that it's not a hardware issue with the speakers.

So my forst step, naturally, was to make sure everything was seated correctly as far as speaker cables and such. Then I asked around a bit and found out that the ATI cards install an audio driver for the HDMI output, so I went through that sound options to make sure that the on-board sound card was still the default device; it is. Next I went in to the device manager and disabled the ATI audio driver, still no help. The only option I saw left was to reinstall the sound drivers, but when I went to uninstall the Realtek drivers, I got a generic '-500 runtime' error. So I booted into the BIOS, disabled the sound card, booted into safe mode, uninstalled the driver, rebooted into BIOS, activated the card, then went through the normal channels to reinstall the Realtek drivers. Now I'm back to square one with only sound out of the left channel. So... failing all this, I decide to go for the whole shebang. I rebooted to safe mode and uninstalled EVERYTHING. I stripped the drivers for the board, chipset, soundcard and video card. I then checked for any ghost or hidden drivers through device manager, and rebooted to Windows; installing all the drivers from scratch. And as you can guess... still no help!

Can anyone tell me what is going on here!? I've plugged the speakers in to my iPod and they work just fine. The on-board sound was running perfectly before I swapped out the video cards, so I can't see it being that. I have no other cards plugged in to expansion ports, so it's not a conflict with another device. It HAS to be a driver issue of some kind but I can't figure it out!

Motherboard: GA-M57SLI-S4 (onboard sound)

Video: ASUS EAH4850

*Note* I'm using the drivers that came with the disk for the video card.(8.500.0.0) I've tried with the latest drivers, and with and without the software suite that's included. The HDMI drivers seem to install no matter what.

Hi,

my friend's onboard sound was half dead like yours (left channel ok only) in a power outage.

So you may have killed yours with static while installing your new videocard.

You can buy a new soundcard or ask an RMA with gigabyte.

Try to install the old videocard too.

Brad