There were a few vendor-specific VLBish busses: Opti local bus was the most common, and had a few different boards: https://ancientelectronics.wordpress.com/ta

There were a few vendor-specific VLBish busses: Opti local bus was the most common, and had a few different boards: https://ancientelectronics.wordpress.com/tag/opti-local-bus/ https://ancientelectronics.wordpress.com/tag/opti-local-bus/ Gigabyte had one that was only used for the "GA-486US" motherboard. The connector was just two 16bit ISA cards back to back: https://theretroweb.com/motherboard/image/ga-486us-front-60b901d42a0c9105852865.jpg https://theretroweb.com/motherboard/image/ga-486us-front-60b... I believe there were some others from different vendors. The signaling for all of these was pretty similar to VLB, since it was just the 486 bus on a connector.