one example https://www.youtube.com/watch?v=a7Qq0pqg-QI
https://theretroweb.com/motherboards/s/fic-486-vip-io https://theretroweb.com/motherboards/s/fic-486-vip-io2
there is also awful fake cache PC-CHIPS M919 https://theretroweb.com/motherboards/s/pcchips-m919-ver-3.4b
another https://theretroweb.com/motherboards/s/u-board-green-vip
even pentium one https://theretroweb.com/motherboards/s/mitac-trigon-pb5500c

rasz_pl wrote on 2023-09-28, 12:24:

there is also awful fake cache PC-CHIPS M919 https://theretroweb.com/motherboards/s/pcchips-m919-ver-3.4b

The fake cache and the whole ethos behind it is indeed awful, but the board (especially once a genuine cache module is used with it) is actually rather good IMO.

Yes !

I have this one...
https://theretroweb.com/motherboards/s/pcchips-m919-ver-3.4b

Whoa! 😳 fake cache guys!!

🤣

Thank governments. Taxes too high. Companies had to fake cache to workaround.

VLB and PCI wasn't super common, but there were some that existed.

Even some boards like this Asus PVI-486SP3 that had PCI, VLB and built in I/O controllers, all on one board.

Back in the era, I encountered some claims that those "VIP" boards are inevitably slower than pure ISA+VLB or ISA+PCI ones.
Supposedly, making VLB and PCI work together requires some delays somewhere.
Is that true?
Or yet another legend, with the possible origin of many VIP boards being actually slower, but only due to the fake cache?

VLB had a Short life between 1993-95 mainly.

If you plan on building a 486 computer I would go with an ISA motherboard or PCI.
PCI motherboard will provide best performance and will be less expensive to build with Newer bios too.
“Luck Star LS-486 motherboard” with “AMD 5x86-133 CPU”
Windows 95 computer.

This was the Budget computer CPU/Motherboard upgrade combo being sold to 486 computer owners that wanted to upgrade
Their computers so they could run Win95.

Intel486dx33 wrote on 2023-09-28, 14:40:

VLB had a Short life between 1993-95 mainly.

If you plan on building a 486 computer I would go with an ISA motherboard or PCI.
PCI motherboard will provide best performance and will be less expensive to build with Newer bios too.

There are different goals for different builds. Best performance may not always be desirable nor going with PCI if one is specifically targeting ISA or VLB hardware.

Personally, I like ISA+VLB systems because you can get greater performance from VLB based I/O controllers coupled with more ISA slots for things like multi-sound card builds.

Grzyb wrote on 2023-09-28, 12:54:

Back in the era, I encountered some claims that those "VIP" boards are inevitably slower than pure ISA+VLB or ISA+PCI ones. Supp […]
Show full quote

Back in the era, I encountered some claims that those "VIP" boards are inevitably slower than pure ISA+VLB or ISA+PCI ones.
Supposedly, making VLB and PCI work together requires some delays somewhere.
Is that true?
Or yet another legend, with the possible origin of many VIP boards being actually slower, but only due to the fake cache?

Certainly wasn't fake cache as PC Chips did that with ISA, ISA/PCI and ISA/VLB only boards too...

Thing is, with VLB and PCI, only one can directly interface with the CPU. VLB would be the obvious choice as it is essentially just the 486 CPU bus - but it is vey limited in number of devices: 1 or 2 easily, a 3rd generally only with wait states, and a PCI controller counts as a device. So if you run PCI of VLB, you will almost always need those wait states, which slow it down vs VLB with just 1 or 2 devices.

You can also use a native PCI chipset and run the VLB off the PCI bus. As PCI isn't electrically limited the way VLB is that is a robust solution, but the PCI bus only runs at 33MHz, meaning that you then lose 40/50MHz VLB operation (or you do have it, but everything just gets bottlenecked at the bridge chip).

So there's always a compromise involved. Note however that you'll frequently hit the same bottlenecks with VLB-only (wait states if you run more than 2 devices and/or run at high clock speeds) or PCI-only (that PCI VGA card is also limited to 32b, 33MHz), so in practice I doubt it makes much difference. What does make a difference is the fact that those VIP-IO boards are some of the most complicated boards to configure (manual interrupts for early PCI implementations, wait states for VLB, huge range of late So3 CPUs with different cache, clock and voltage options), and more complexity means more ways to mess it up and configure sub-optimally. I strongly suspect that played a bigger role than inherent hardware limitations.

In addition, in the case of Pentium VIP-IO chipsets, the ones that supported it were glacially slow to start with; it was OPTi's niche, and they had excellent 486 chipsets, but until the Viper-M (which was ISA/PCI only and above all too little, too late) their Pentium chipsets were abominably slow regardless of which buses they used.

dionb wrote on 2023-09-28, 17:38:

Certainly wasn't fake cache as PC Chips did that with ISA, ISA/PCI and ISA/VLB only boards too... […]
Show full quote

Grzyb wrote on 2023-09-28, 12:54:

Back in the era, I encountered some claims that those "VIP" boards are inevitably slower than pure ISA+VLB or ISA+PCI ones. Supp […]
Show full quote

Back in the era, I encountered some claims that those "VIP" boards are inevitably slower than pure ISA+VLB or ISA+PCI ones.
Supposedly, making VLB and PCI work together requires some delays somewhere.
Is that true?
Or yet another legend, with the possible origin of many VIP boards being actually slower, but only due to the fake cache?

Certainly wasn't fake cache as PC Chips did that with ISA, ISA/PCI and ISA/VLB only boards too...

Thing is, with VLB and PCI, only one can directly interface with the CPU. VLB would be the obvious choice as it is essentially just the 486 CPU bus - but it is vey limited in number of devices: 1 or 2 easily, a 3rd generally only with wait states, and a PCI controller counts as a device. So if you run PCI of VLB, you will almost always need those wait states, which slow it down vs VLB with just 1 or 2 devices.

You can also use a native PCI chipset and run the VLB off the PCI bus. As PCI isn't electrically limited the way VLB is that is a robust solution, but the PCI bus only runs at 33MHz, meaning that you then lose 40/50MHz VLB operation (or you do have it, but everything just gets bottlenecked at the bridge chip).

So there's always a compromise involved. Note however that you'll frequently hit the same bottlenecks with VLB-only (wait states if you run more than 2 devices and/or run at high clock speeds) or PCI-only (that PCI VGA card is also limited to 32b, 33MHz), so in practice I doubt it makes much difference. What does make a difference is the fact that those VIP-IO boards are some of the most complicated boards to configure (manual interrupts for early PCI implementations, wait states for VLB, huge range of late So3 CPUs with different cache, clock and voltage options), and more complexity means more ways to mess it up and configure sub-optimally. I strongly suspect that played a bigger role than inherent hardware limitations.

In addition, in the case of Pentium VIP-IO chipsets, the ones that supported it were glacially slow to start with; it was OPTi's niche, and they had excellent 486 chipsets, but until the Viper-M (which was ISA/PCI only and above all too little, too late) their Pentium chipsets were abominably slow regardless of which buses they used.

↑
Dude!

Intel486dx33 wrote on 2023-09-28, 14:40:

VLB had a Short life between 1993-95 mainly.

If you plan on building a 486 computer I would go with an ISA motherboard or PCI.

I disagree... ISA only is for 386 builds... For 486 you should use a VLB build. Ideally you want a graphics adapter that will tolerate 0WS, and a Cyrix 5x86 is the icing on the cake, which will allow you to alternate between a fast 486 and a slow 486 with SETMUL.

hm depends on what you play.
320x200 @256 Colors needs only around ~ 2Mbyte/s throughput for fluid playing.

i played Terminator Futureshock with GD5424 ISA Card just fine on AM5x86 133Mhz without L2 Cache.

A couple of years ago I actually had one of those motherboards in a system I found on the side of the road , but I sold the system since I didn't know what it was worth at the time.

Its configuration had a pci video card in it so I guess nobody bothered using the vlb.

My cheap computer shopper AMD 5x86 system supposedly had 60ns EDO, a 1.2gb HD and a mid range PCI graphics card (2mb) forgetting the exact model, might have even had very mediocre 3D acceleration.

XING MPEG acceleration and software was a selling point.

Was a nice rig but came with the PCCHIPS motherboard which developed bad serial ports so I ended up installing an antique serial card

AppleSauce wrote on 2023-09-28, 22:44:

A couple of years ago I actually had one of those motherboards in a system I found on the side of the road , but I sold the system since I didn't know what it was worth at the time.

That's the Asus PVI-486SP3 motherboard I posted earlier.

Recent Ebay sales have this board going for around $300 USD.

Shponglefan wrote on 2023-09-28, 15:56:

Intel486dx33 wrote on 2023-09-28, 14:40:

VLB had a Short life between 1993-95 mainly.

If you plan on building a 486 computer I would go with an ISA motherboard or PCI.
PCI motherboard will provide best performance and will be less expensive to build with Newer bios too.

There are different goals for different builds. Best performance may not always be desirable nor going with PCI if one is specifically targeting ISA or VLB hardware.

Personally, I like ISA+VLB systems because you can get greater performance from VLB based I/O controllers coupled with more ISA slots for things like multi-sound card builds.

There's also another factor.
With PCI came technologies like the Pentium (586), Plug&Play BIOS and ACPI and APIC.

The 486 platform with ISA or ISA+VLB thus is the last "pure" PC/AT generation with maximum compatibility to the DOS world.

While later board generations can of course still run DOS and games, they're nolonger focusing on the standards of the DOS days (and Windows 3.x days, thus) but those of the Windows 95 days.

You'll notice this when you're trying to run very picky OSes from the late 80s, who made very strict assumptions on the underlying hardware.
Like an old copy of Unix/Xenix or OS/2.

Anyway, this is just a reminder. A 486 board which has PCI "tacked on" (attached via VLB), it may look like an ordinary 486 board to software - with the exception to the additional PCI support via BIOS.

Shponglefan wrote on 2023-09-28, 23:45:

AppleSauce wrote on 2023-09-28, 22:44:

A couple of years ago I actually had one of those motherboards in a system I found on the side of the road , but I sold the system since I didn't know what it was worth at the time.

That's the Asus PVI-486SP3 motherboard I posted earlier.

Recent Ebay sales have this board going for around $300 USD.

Ouch that smarts , well there ya go. I guess I got it for free and did make a pure profit on it so could be worse.

One thing I dislike about PCI on a 486 is the inability to use your own IDE controller (unless it has its own boot ROM). You're stuck with your motherboard's IDE implementation. With VLB, the IDE part is controlled through the BIOS and with a driver. When PCI IDE is not implemented properly in the BIOS, the speeds can be very slow, much slower than a good VLB drive.

Yeah 486 with PCI is garbage IMHO and just cobbled together to say "hey look what we have". 🤣