The CMedia CMI8738 PCI SX driver enables Windows to communicate with your PCI audio card, allowing software to use its playback and recording functions. If sound is missing after a Windows installation or the card appears as an unidentified multimedia device, installing a matching driver may restore normal operation.

Key Features

• Audio playback support: Provides the driver interface needed to send sound from applications, music players, and games to the card’s connected audio outputs.
• Recording input access: Allows compatible programs to use the card’s available microphone or line-in connections, depending on the hardware configuration.
• Windows audio integration: Helps the operating system recognize the CMedia CMI8738 PCI SX and expose its supported playback and recording devices in sound settings.
• Device configuration: Makes supported audio controls available through Windows and, where included in the package, a CMedia configuration utility. Available options depend on the driver version and card design.

How to Install

1. Check your Windows version and hardware. Confirm whether you are running Windows 11, 10, 8, or 7, and check whether the system is 32-bit or 64-bit. In Device Manager, verify that the audio card’s hardware ID matches the driver package. Compatibility can vary for older PCI hardware, so do not assume one package supports every listed Windows version.

1. Download and extract the matching package. Choose a driver intended for your operating system and architecture. If the download is compressed, extract its contents to a folder you can easily locate.

1. Install the driver. Run the included installer as an administrator and follow its prompts. If there is no installer, open Device Manager, right-click the audio card or unidentified multimedia device, select Update driver, and browse to the extracted folder.

1. Restart the computer. Reboot when prompted so Windows can load the installed audio components. If Windows rejects the driver as incompatible or unsigned, obtain a suitable package rather than disabling security protections.

1. Select and test the audio device. Open Windows sound settings and choose the CMedia card as the playback device if needed. Test your speakers or headphones, then check recording inputs if you use them. If audio remains silent, verify the cable connections, volume levels, and Device Manager status.

Common Issues and Fixes

• Install fails or rolls back: The CMI8738 package is legacy and often unsigned on Windows 10/11. Run setup as administrator in Windows 7 compatibility mode; if blocked, use Device Manager > Update driver > Browse to the extracted driver, or temporarily disable driver signature enforcement only for a trusted CMedia package.
• Device not detected: Power off, reseat the PCI card, and try another PCI slot. Check Device Manager for an Unknown Device or “C-Media PCI Audio Device”; install chipset/PCI drivers and confirm the card is enabled in BIOS. Missing hardware in Device Manager usually means slot/contact or card failure.
• Version conflicts: Remove any existing CMI8738 or generic audio driver first: Device Manager > Sound controllers > Uninstall device > Delete driver software. Reboot before installing the correct 32/64-bit CMedia package, and avoid mixing it with Realtek/HD Audio drivers.