Depends. To begin with, the difference between them is small and performance can fluctuate on motherboards with identical chipset. SIS496/497 can work on 66 MHz FSB with 66 Mhz PCI bus on certain boards though.

fargo wrote on 2021-12-26, 01:40:

I was going to get the SiS board based on its features, but read an article (here) saying the SiS chipset is slower and not the best option for 486.

Did you read the update there as well? Where it says that a wrongly set turbo jumper/switch was to blame.

I have all the respect for Michal Necasek, but this particular article is off.
That SIS board is incomparable to Alaris Cougar.
It is just a next-gen product on a different level.

SIS 496/497 is the better 486 chipset compared to UMC UM8881.
But make sure you pick the right motherboard.

gerwin wrote on 2021-12-26, 02:53:

Did you read the update there as well? Where it says that a wrongly set turbo jumper/switch was to blame.

Yes, but even after fixing that, the performance wasn’t top notch.

pshipkov wrote on 2021-12-26, 05:12:

SIS 496/497 is the better 486 chipset compared to UMC UM8881.
But make sure you pick the right motherboard.

I found exactly the same motherboard mentioned in the article.

Be sure that it has a PS/2 mouse port or connector.

Disruptor wrote on 2021-12-26, 13:23:

Be sure that it has a PS/2 mouse port or connector.

Is this related to performance or just for use convenience?

fargo wrote on 2021-12-26, 13:54:

Disruptor wrote on 2021-12-26, 13:23:

Be sure that it has a PS/2 mouse port or connector.

Is this related to performance or just for use convenience?

That depends on the point of view.

As a former semi professional gamer I would say that optical mice improve gaming skills and performance over wheel-based mice.

Disruptor wrote on 2021-12-26, 14:44:

As a former semi professional gamer I would say that optical mice improve gaming skills and performance over wheel-based mice.

Ah, I see. Thank you

A stock 4SAW2 motherboard will most definitely lose, in terms of performance, to more known motherboard manufacturers which used the same chipset. This motherboard has a few questionable chipset features/BIOS option implementations, but the main drawback for it is a badly implemented L2 cache policy settings in older BIOS revisions, which would result in a much lower RAM/L2 throughput than this chipset is supposed to deliver.

A properly modded 4SAW2 will fly high, here are some results of 4SAW2 with an am5x86 clocked at 175MHz (58.3x3), 8MB FPM RAM and lowest possible RAM/L2 timings this chipset can handle:

Interesting! I've seen several BIOS versions over the internet for the 4SAW2, and even an Asus bios modded for it. Would a simple BIOS update fix this board's performance?

Yes, its main issue is omitted chipset options in BIOS, though, official BIOS could be fixed with a "Modbin" BIOS editor.

VLB performance should not be underestimated. After all it was a much simpler bus and it had direct access to 486 memory bus.

Rather than performance which should be similar, I would consider whether you will be taking advantage of:
- PCI IRQ sharing - allows to install more expansion cards
- larger selection of PCI expansion cards which are newer and have more memory. You could use a 3D graphics card in 486.
- the board will likely come with AWARD BIOS which supports larger drives than those old non-LBA AMI BIOSes
- PCI PnP (not a big advantage in my opinion)

I would also vouch for PS/2 mouse connector due to ability to use optical mouse.

If you would benefit from the above advantages then I would pick PCI board even if it had slightly worse performance than VLB board.

AlexZ wrote on 2021-12-26, 21:27:

If you would benefit from the above advantages then I would pick PCI board even if it had slightly worse performance than VLB board.

Both boards have PCI; one has VLB in addition.

I went ahead and ordered the Soyo board with SiS496 chipset. From the feedback I got here, it seems the better option compared to the UMC board.