Creative SB128 CT5803

Creative Sound Blaster PCI 128, model CT5803 from 1999

 ES1373, http://www.hardwaresecrets.com/datasheets/es1373.pdf
AC'97 digital controller with DOS compatibility. Interfaces for AC'97 codec, I2S and SPDIF.
Chip was developed by Ensoniq, company known also for their keyboards/synthesizers. Ensoniq was acquired by Creative in January 1998.

 78L05 and 79L05 as voltage regulators for analog part.
I'm definitively not a picky listener, but this cards sounds bad because of poor voltage filtering. When I was using it in my old Celeron 466MHz PC I was even able to hear mouse moving. These two blue capacitors were helping, "digital noise" was reduced to not noticeable (solder got broken when stored).

 Cirrus Logic CS4297A-JQ - AC'97 codec

 NJM4565 dual opamp

Few extra audio inputs and optional power amplifier on board.