I know that VLB bus is tied to the 486 architecture

VLB is not tied to 486 specifically, it is tied to FSB which was present on 386DX and 486 platform. Socket 4/5 motherboards most likely routed it through PCI.

VLB was a cludge during a specific timeframe when faster bus options were too expensive and ISA was too slow. A 64 bit 66mhz VLB 2 was developed but nobody adopted it.

Even though it was present on boards 1992-1996 it had very little attention after 1993 which really stumped owners of systems with vlb wasting their investment.

Comparatively PCI (1993) had an extremely long life.

But VLB you didn’t have many upgrade options, I upgraded out of my 1995 era VLB dx2-66 to a 5x86 pci system just due to vlb vrs pci video options, basically sold the dx2 for what I paid for it and moved to a cheaper much faster 5x86.

There simply wasn’t much VLB related circa 1996, unfortunate but just how it was.

rmay635703 wrote on 2023-09-09, 18:02:

Even though it was present on boards 1992-1996 it had very little attention after 1993 which really stumped owners of systems wi […]
Show full quote

Even though it was present on boards 1992-1996 it had very little attention after 1993 which really stumped owners of systems with vlb wasting their investment.

Comparatively PCI (1993) had an extremely long life.

But VLB you didn’t have many upgrade options, I upgraded out of my 1995 era dx2-66 to a 5x86 pci system just due to vlb vrs pci video options, basically sold the dx2 for what I paid for it and moved to a cheaper much faster 5x86.

There simply wasn’t much VLB related circa 1996, unfortunate but just how it was.

I don't know much about VLB - did your typical brand-name computer have VLB slots? Certainly the 1995-era 486 AST I had didn't have any slots other than ISA and it had a soldered video controller that was hooked up... who knows to what bus... and my vague recollection is that most of the Aptivas or Compaqs or Packard Hells at the time were similar...

If VLB cards were primarily used by clone shop AT systems, that could explain why VLB had such a short life?

Having shopped for 486 systems including name brands 1994-1995 I would say pretty much every name brand plastered
VESA LOCAL BUS GRAPHICS all over the sales card in front of the machine at the store.

So Many name brand 486 systems had VESA local bus.
I would agree Most didn’t have a slot.

That said I can personally attest that Micronics/Micron definitely offered boards with VLB slots retail and Micronics boards were found in several name brands including gateway

From a technical standpoint VLB was super crap. The cards have to be very long. That makes them (more) expensive to produce. Fitting them required a lot of force. And you have a lot more pins than ISA or PCI that have to make perfect contact.
I can fully understand that nobody wanted it as soon as PCI was in sight, wich was basically the same time VLB was released...
That only 486 natively "speak" VLB didnt help it either...
To be fair i am surprised that we even have the amount of VLB stuff today. It was already dead when it arrived...

JustJulião wrote on 2023-09-09, 17:27:

...I'm curious about SBCs though. There are newer VLB SBCs (socket 7, 370...). ...

Are you sure that they are VLB?
My SBCs just have the PCI connector after the ISA connector to get it on the backplane. That doesnt say its VLB.

Here vou can see the PCI part of the SBC after the ISA slot is just routed to normal PCI slots. It looks a little bit like VLB but it isnt.

VivienM wrote on 2023-09-09, 18:06:

rmay635703 wrote on 2023-09-09, 18:02:

Even though it was present on boards 1992-1996 it had very little attention after 1993 which really stumped owners of systems wi […]
Show full quote

Even though it was present on boards 1992-1996 it had very little attention after 1993 which really stumped owners of systems with vlb wasting their investment.

Comparatively PCI (1993) had an extremely long life.

But VLB you didn’t have many upgrade options, I upgraded out of my 1995 era dx2-66 to a 5x86 pci system just due to vlb vrs pci video options, basically sold the dx2 for what I paid for it and moved to a cheaper much faster 5x86.

There simply wasn’t much VLB related circa 1996, unfortunate but just how it was.

I don't know much about VLB - did your typical brand-name computer have VLB slots? Certainly the 1995-era 486 AST I had didn't have any slots other than ISA and it had a soldered video controller that was hooked up... who knows to what bus... and my vague recollection is that most of the Aptivas or Compaqs or Packard Hells at the time were similar...

If VLB cards were primarily used by clone shop AT systems, that could explain why VLB had such a short life?

A lot of those 486SX/486DX2 era mass market systems that used LPX and a riser card, had no VLB slots but nonetheless the onboard VGA and IDE was electrically VLB

DerBaum wrote on 2023-09-09, 19:07:

From a technical standpoint VLB was super crap. The cards have to be very long. That makes them (more) expensive to produce. Fit […]
Show full quote

From a technical standpoint VLB was super crap. The cards have to be very long. That makes them (more) expensive to produce. Fitting them required a lot of force. And you have a lot more pins than ISA or PCI that have to make perfect contact.
I can fully understand that nobody wanted it as soon as PCI was in sight, wich was basically the same time VLB was released...
That only 486 natively "speak" VLB didnt help it either...
To be fair i am surprised that we even have the amount of VLB stuff today. It was already dead when it arrived...

The way I understood it was that people were already coming up with ways to hook things to the 486 local bus (Weitek 4167, OPTi Local Bus) and VLB was about codifying practice, establishing a standard connector as quickly as possible before more of these custom ones splintered, and adding some features that video cards don't use like DMA/bus mastering. Or in other words what you describe was well-known and it was not supposed to be any more than that (perhaps minds changed resulting in VLB v2.0?) I wonder how many "VLB" video chips were in development before VLB was even standardized but required no changes to work once it was established?

VLB doesn't require BIOS changes more than any other chipset tweaking options but PCI requires a ton. Perhaps that is also why VLB lingered for a while.

jakethompson1 wrote on 2023-09-09, 20:26:

VLB doesn't require BIOS changes more than any other chipset tweaking options but PCI requires a ton. Perhaps that is also why VLB lingered for a while.

Circa 1993 PCI was extraordinarily expensive to include from a boardmakers standpoint. (It was only trying to be cheaper than mca)

There was licensing, custom chips, bios and even the slot itself was expensive.

VLB was made using a cheap commodity connector, licensing and bios were non-issues.
It was as close to a free upgrade as possible and was compatible with 286/386/486 buses out of the box.

The “size” of the VLB isn’t really a concern either in that era, ISA cards were many times longer and most era specific vlb cards managed to fill every square inch with components, those that didn’t were usually long skinny (1” tall) affairs .

VLB 2 was real but pci was too embedded at that point to care

The Serpent Rider wrote on 2023-09-09, 17:47:

VLB is not tied to 486 specifically, it is tied to FSB which was present on 386DX and 486 platform. Socket 4/5 motherboards most likely routed it through PCI.

Funnily enough, it's the other way around, PCI worked using a bridge 82C822 chip to VLB (at least on Opti boards, not sure if the Toshiba laptops had any PCI stuff). So I guess technically all PCI devices there were the third VLB device. So extra latency for PCI, but I suppose some of it could be eliminated if you simply didn't use any actual VLB stuff (haven't tested myself though). However, looking at reviews from the magazine from the time, 99% of prebuilt systems with those chipsets would pair a PCI video card with a VLB disc controller.

The VLB bus gets the clock either through a divider from the main clock, or through a separate clock chip.

DerBaum wrote on 2023-09-09, 19:12:

Are you sure that they are VLB? My SBCs just have the PCI connector after the ISA connector to get it on the backplane. That doe […]
Show full quote

JustJulião wrote on 2023-09-09, 17:27:

...I'm curious about SBCs though. There are newer VLB SBCs (socket 7, 370...). ...

Are you sure that they are VLB?
My SBCs just have the PCI connector after the ISA connector to get it on the backplane. That doesnt say its VLB.

14-slot-backplane-with-4-pci-slots-and-8-isa-slots-backplane.jpg

Here vou can see the PCI part of the SBC after the ISA slot is just routed to normal PCI slots. It looks a little bit like VLB but it isnt.

You are obviously right. It's a way to not be bottlenecked by ISA, while maintaining compatibility. That explains why what I thought was VLB is much more common on newer SBCs. I guess it's solved then, I'll try to find my first Socket 3 motherboard.

I'm new to 486 era stuff (I'm a bit "too young", my very first PC was PII 450 based) but I want my 486 rig.

I've been curious about ISA sound cards (because they look baddass), then by the games taking advantage of it, then I learned about speed sensivity (I know there are easy workarounds on newer platforms, but It's the excuse I needed to get "real hardware"), and, finally, VLB cards, for the same reason as sound cards and because I like obscure stuff in general.
I also like how 386/486 era pc cases look, I don't have any.
The SiS 471 is pretty standard and fast, but I'm also attracted by Symphony Wagner and ALi M1429 chipsets, for the sake of "exoticity".

As others already mentioned VLB bypasses chipset, cards are wired directly to CPU data/address bus. As long as you have fast 486 you are good to go.

rmay635703 wrote on 2023-09-09, 21:00:

Circa 1993 PCI was extraordinarily expensive to include from a boardmakers standpoint. (It was only trying to be cheaper than mca)
There was licensing, custom chips, bios and even the slot itself was expensive.

Licensing is a non issue, PCI-SIG had ~same annual payments as VESA. Bios is fixed cost. Afaik slot is the same reused MCA molding as in VLB.
What did cost was newer chipsets.

Early PCI got bad rep due to broken PCI IDE controllers: "While not an actual Intel chipset bug, the Mercury and Neptune chipsets could be found paired with RZ1000 and CMD640 IDE controllers with data corruption bugs.". There also were problems with bus mastering and interrupt sharing/steering in early Intel PCI chipsets. Imagine getting PCI board and having to set PCI interrupts with jumpers.

rmay635703 wrote on 2023-09-09, 21:00:

VLB was made using a cheap commodity connector

reusing MCA molds just like PCI 😀

rmay635703 wrote on 2023-09-09, 21:00:

was compatible with 286

yeah, we will need a little bit more info on that one

rmay635703 wrote on 2023-09-09, 21:00:

The “size” of the VLB isn’t really a concern either in that era, ISA cards were many times longer and most era specific vlb cards managed to fill every square inch with components, those that didn’t were usually long skinny (1” tall) affairs.

Even skinny ones were over 2x pci surface area. 4 layer pcb costs add up quickly. PCI allowed manufacturing $10 PCI cards at a profit.

Anyone know if the "Designed for Windows 95" logo program required a PCI bus?

rasz_pl wrote on 2023-09-10, 00:37:

Licensing is a non issue, PCI-SIG had ~same annual payments as VESA. Bios is fixed cost. Afaik slot is the same reused MCA molding as in VLB.
What did cost was newer chipsets.

I don't know how BIOS licensing costs worked--did AMI, Award, Phoenix license a BIOS for some old chipset like UM481 for a cut rate price while marking up Intel 420TX/ZX/EX w/PCI? Or did they all cost about the same regardless of chipset due to competition between the three?

I bet anything EISA was marked up as a premium feature though.

JustJulião wrote on 2023-09-09, 23:31:

I'm new to 486 era stuff (I'm a bit "too young", my very first PC was PII 450 based) but I want my 486 rig.

It's less about the hardware and more about the software - that PII 450, that probably ran... Win98?

Your 486, I presume, you're going to want to go DOS (and to a small extent Windows 3.1?)? (You can run Win95 on a 486 just fine, but why would you want to 28 years later?) If so... well, that'll be a fun learning curve 😀 Welcome to the world of pre-PnP, DOS conventional memory management (I still remember the sense of accomplishment coming from getting... I think it was 633 or 634K... using QEMM), config.sys files, etc.

And the crazy thing is, I only did DOS for 6 months - was a Mac guy prior to 1995 (and would have stayed a Mac guy if my dad hasn't wisely seen the trends in the industry), then bought Win95 at retail on launch day, Aug. 24, 1995. But I still have the memories of learning all that DOS stuff.

That being said, at least you're doing it as a retro hobby project, kinda like restoring a 1960s car instead of trying to daily drive one, so you don't have to worry about locking your parents out of the family computer if your newest addition to autoexec.bat doesn't do what you hoped for... 😀 Or being unable to boot because QEMM 7.01 or 7.02 wiped your CMOS settings in the pursuit of that extra 2K of conventional memory.

VivienM wrote on 2023-09-10, 01:12:

It's less about the hardware and more about the software - that PII 450, that probably ran... Win98? […]
Show full quote

JustJulião wrote on 2023-09-09, 23:31:

I'm new to 486 era stuff (I'm a bit "too young", my very first PC was PII 450 based) but I want my 486 rig.

It's less about the hardware and more about the software - that PII 450, that probably ran... Win98?

Your 486, I presume, you're going to want to go DOS (and to a small extent Windows 3.1?)? (You can run Win95 on a 486 just fine, but why would you want to 28 years later?) If so... well, that'll be a fun learning curve 😀 Welcome to the world of pre-PnP, DOS conventional memory management (I still remember the sense of accomplishment coming from getting... I think it was 633 or 634K... using QEMM), config.sys files, etc.

And the crazy thing is, I only did DOS for 6 months - was a Mac guy prior to 1995 (and would have stayed a Mac guy if my dad hasn't wisely seen the trends in the industry), then bought Win95 at retail on launch day, Aug. 24, 1995. But I still have the memories of learning all that DOS stuff.

That being said, at least you're doing it as a retro hobby project, kinda like restoring a 1960s car instead of trying to daily drive one, so you don't have to worry about locking your parents out of the family computer if your newest addition to autoexec.bat doesn't do what you hoped for... 😀 Or being unable to boot because QEMM 7.01 or 7.02 wiped your CMOS settings in the pursuit of that extra 2K of conventional memory.

I went back as far as a PMMX/Voodoo/W95 rig I made, but I stayed away from older stuff for that very reason, although I had to use DOS sometimes and I have to run some early 3D games from DOS mode. I'm a bit concerned about the I/O card, I suppose I'll have to add its drivers on one of the DOS install floppies. The other thing about I/O is that I plan to overclock to 40MHz, and I know that PCI IDE controllers don't like overclocked buses, I expect even more issues on a VLB I/O controller. I'll have to choose it carefully.
For DOS itself, I'll use tools and packs of tools that will make my life easier, like Phil's starter pack or "REMOVED" on REMOVED that looks promising. I'll test FreeDOS too at some point.
I'll go deeper afterwards but I want to get to know DOS by the easier end.

jakethompson1 wrote on 2023-09-10, 00:53:

Anyone know if the "Designed for Windows 95" logo program required a PCI bus?

most likely no, I do know that at some point (~2001?) Windows logo required APIC https://community.osr.com/discussion/21604

rasz_pl wrote on 2023-09-10, 02:07:

jakethompson1 wrote on 2023-09-10, 00:53:

Anyone know if the "Designed for Windows 95" logo program required a PCI bus?

most likely no, I do know that Windows logo required APIC https://community.osr.com/discussion/21604 and that would limit you to intel chipset 486, but still cover EISA/ISA.

APIC required in 1995? no way. I think that is for a newer "Designed for" program (like XP or something) or perhaps one of those PC 97 things.

I know you could comply even with 486 UM8881 as I had such a system with the logo. I believe a Plug and Play BIOS was required also.

Even without the stick of the Designed for Windows 95 program, a "carrot" is that DOS/WfW 3.11 would not have taken advantage of any PCI features like grabbing the vendor/device ID and finding or asking for drivers, but Win95 would. So extra motivation to get PCI in place before Win95 whereas WfW 3.11 users wouldn't notice.

edit: ah, I see your edit. Since no original sources are coming up, I'm going to see if any magazine articles from that time might have listed what "Designed for Windows 95" required. I vaguely recall reading about it before, including the obvious things like no ISA video cards.

sorry, ninja edited my post from under you