This is the chip: https://theretroweb.com/chips/10029

I've only seen it on VLB combo IDE / VGA cards. The VGA chip is usually a Cirrus GD5428.

If you have one, can you check to see if works with the Adaptec ADI/2 Flex!Driver ?

http://vogonsdrivers.com/getfile.php?fileid=2046