i820 Motherboard Roundup - January 2000

One of the major OEM pushes towards the i810 chipset upon its introduction was its support for Audio/Telephony Codecs to be integrated onto the motherboard.  That level of integration has been pushed over onto the i820 motherboard market as well.  While the i820 chipset is much less of an integrated motherboard solution than the i810 was (no integrated video), to OEMs, the more you can put on a motherboard the cheaper the overall cost of the system will be and the more profit the OEMs can enjoy.

Most i820 motherboards that take advantage of the Audio Codec ’97 support of the i820 chipset will feature an AC’97 controller placed on the motherboard that drives an integrated audio output while supporting the use of the AMR (Audio Modem Riser) slot for higher quality audio or modem support.  The reason for the use of the AMR slot is to place the more sensitive components on an AMR slot so that motherboard manufacturers don’t have to increase the production time of their products because of the certification required for sensitive analog components such as those on modems or higher quality audio devices.  This is also why, in spite of the presence of the AMR slot, the motherboard manufacturers will go ahead and include audio inputs/outputs on the motherboard itself, so they don’t have to worry about the certification time required by an AMR card in order to ship their boards to OEMs with integrated sound.

Remember that these AC’97 controllers depend on the host CPU to do most of the work associated with their particular tasks, but because of this they add a negligible amount to the final cost of the motherboard. 

Most motherboards we have seen make use of the Analog Devices 1881 Soundport Codec or the Cirrus Logic CrystalClear SoundFusion AC’97 controller; however, according to Intel, the following manufacturers produce AC’97 controllers for use with the i820 chipset in providing both soft audio and modem support:

• Analog Devices
• Crystal
• IC Ensemble, Inc.
• Motorola
• SigmaTel, Inc.
• Smart Link

If you would rather use your sound card (an option that most Vortex2 or SB Live! owners will want to take), then rest assured that you’ll have no problem disabling the on-board AC’97 controller either through the BIOS setup or through an on-board jumper.  We have yet to encounter a motherboard that failed to allow us the option of disabling the on-board AC’97 controller.