EISA vs OPTi Local Bus cards - how to tell

Did anyone ever benchmark identical video cards on the different buses?

AKA ISA VRS VLB VRS OPTI?

I’ve always been curious if there was much different

My experience with the opti local bus was with OEM motherboards that had onboard video and IDE on said bus (but just ISA expansion)

I have a 386 board with an unsoldered OLB slot. I haven't bothered to solder it on because OLB cards are hard to find, and most of them aren't that great. I think at best you might be able to find an S3 928...or maybe a Mach32. I've seen special proprietary mach32s for other weird buses, so I assume one for OLB probably exists.

joonicks wrote on 2021-10-26, 23:36:

486DX-50

If it's really 486DX-50, and not 486DX2-50, then the FSB is 50 MHz.
50 MHz was a major problem for VESA Local Bus, and so it must've been for Opti Local Bus.
You were lucky if you got it all working without any issues.

I am somewhat confused about the chipset. Im obviously not an expert on chipset but, I recall seeing the same chipset on non-OLB motherboards. I dont actually know what the chipset has to do for a bus to work. One of my maybe naive dreams is to pair an old 486 cpu with modern memory, bypassing the chipset and cache completely and give the cpu direct access to megabytes of 50MHz static ram.

Chipset on my OLB motherboard is UM82C481BF, UM82C482AF and UM82C206F

(Batteries have been removed, no leakage)

There is no OLB chipset. There is also no VLB chipset.
They all are ISA chipsets. (Except in combination with EISA or PCI)

Since they are a smart connection to the 486 FSB, OLB/VLB just needs some extra pins to the slot plus some extra logic.

Yes, I do own some OLB stuff.

HanJammer wrote on 2022-11-23, 20:45:

Yes, I do own some OLB stuff.

The second card is probably not OLB. It just seems to be a CPU card that shares the same connector type. You can see on the motherboard the slot that says "for CPU module only".

Anonymous Coward wrote on 2022-11-24, 15:19:

HanJammer wrote on 2022-11-23, 20:45:

Yes, I do own some OLB stuff.

The second card is probably not OLB. It just seems to be a CPU card that shares the same connector type. You can see on the motherboard the slot that says "for CPU module only".

The second card is the cpu card for the 3rd card (=mainboard)?

Anonymous Coward wrote on 2022-11-24, 15:19:

The second card is probably not OLB. It just seems to be a CPU card that shares the same connector type. You can see on the motherboard the slot that says "for CPU module only".

It is CPU card. Showing the motherboard without this card wouldn't make much sense, would it?