I think it is the opposite way actually. VLB boards are very common for 486 class computers. I found it more rare to see the ISA only systems, and only for very end systems.

486 DX2-66 with VLB graphics are extremely common.

Now some testing I did, showing how VLB advanced graphics performance on 486 computers.

Computer:
486-DX2 66
Asus VL/I-486SVGO VLB board
32meg RAM
240gb hard drive
Winbond VLB I/O controller card
Intel etherexpress 10mbit ISA ethernet

Using a series of graphics cards, from low end ISA to medium end VLB I have done some benchmarks.

3dBench DOS Benchmark:
15.1 fps - Trident 9000i ISA card
30.4 fps - Tseng ET4000 ISA (at 8.25mhz ISA bus)
31.8 fps - Tseng ET4000 ISA (at 11mhz ISA bus, causes artifacts in windows)
48.5 fps - Tseng ET4000 VLB
46.8 fps - Cirrus Logic GD5428 VLB
50.1 fps - S3 804 VLB

Doom max settings (lower ticks are better)
8001 ticks - Trident 9000i ISA
4743 ticks - Tseng ET4000 ISA (at 8.25mhz ISA bus)
4601 ticks - Tseng ET4000 ISA (at 11mhz ISA bus, causes artifacts in windows)
2609 ticks - Tseng ET4000 VLB
2691 ticks - Cirrus Logic GD5428 VLB
2567 ticks - S3 804 VLB

Windows performance - Wintach (at 800 x 600 resolution in 8bit colour)
4.37 times reference - Trident 9000i ISA
12.33 times reference - Tseng ET4000 ISA (at 8.25mhz ISA bus)
12.79 times reference - Tseng ET4000 ISA (at 11mhz ISA bus, causes artifacts in windows)
19.80 times reference - Tseng ET4000 VLB
28.94 times reference - Cirrus Logic GD5428 VLB
31.24 times reference - S3 804 VLB

In subjective terms playing doom on default settings
Trident 9000i - Its possible to play, but you would have to be really desperate because it is a slideshow.
ET4000 ISA - More playable, still rather choppy, If this was the computer I had in the day, I'd play doom this way I guess.
VLB cards - Quite smooth, not perfect FPS but pretty close. Definitely noticeably better than the ISA cards.

I'd definitely recommend avoiding ISA video cards for a 486 class computer.

canthearu wrote:

I think it is the opposite way actually. VLB boards are very common for 486 class computers. I found it more rare to see the ISA only systems, and only for very end systems.

For the first four years of the 486's availability (1989-1993), VLB did not even exist. And VLB had a life-span of not even two years, when it became obsolete just like the 486 did. So while your own observation might be true, ISA-only was standard for most of the 486's life-span. These days, ISA-only board probably turn up less often than VLB boards because they were trashed early, unlike the better VLB or PCI boards.

The 486 wasn't really popular until 1992 or so, when the DX2-66 and VLB was released. So that is probably why you don't see that many 486 ISA only systems.

Not too sure on your dates there. We (Here in semi rural Australia) had 486sx25 and the like around 90ish because that's when the school i went to got them. They were all running dos win3, had about 4meg ram and something like a 150MB HDD. Trident VGA and network cards. They were not much but it was a good representation of what most of us had at home.

My parents bought their first 486DX33 in 92 and that had the typical setup of 4mb ram, s3 ISA graphics (1MB), Creative SB with CD-ROM, ~500MB HDD, 14" No named CRT and a Cannon Printer. It was a very expensive computer at the time. From memory it cost them over A$2K. We upgraded it over time with an extra 4MB ram and the DX2 66 CPU. THis is what most of us had at the time. VLB wasn't a thing for the home user where we were.

The next computer i made them buy because I was in Year 11 was in 1998, It was a P200MMx with 16MB EDO ram, S3 Virge 4MB (Can't recall what one) and Seagate 2GB HDD, ordinary CMI 8330 ISA sound (Replaced by SB very soon after) and running Win98. It was considered to be one of the fastest computers at the time that Normal people would own. The tower itself was about A$1.5K

These are the computers i am recreating,
Why?
Because that had the limitations of the time.

You had the top system in 92, in Melbourne in late 92 my parents bought me a used 286 AT 12mhz I think cga gfx crt etc for $500 aud. Trading games at school on 5 1/4 disks was very exciting

The way i now look at VLB is the same as the 820 chipset with RD Ram (Rambus) for P3, Sure it was quicker than the 810/815 with PC133 SD-Ram but not many people had it because it was expensive.

I dunno -- I agree with canthearu here. Early 486s were expensive because they were new, and didn't offer a whole lot more than similarly-spec'd 386s. My first 486 was an SX25 with ISA only, so yeah I get it, not everyone had VLB. But in many ways, my dad's 386DX33 could trump my 486. When I upgraded the board to VLB with a DX2/66, the tables turned. It may have been a short-lived solution, but it was an extremely prolific one due to the cost of a Pentium for quite some time thereafter.

There's no right answer in the retro hobby. You do what you want. But, rationally (such that any of this is rational, anyway), an ISA 486 is either bottlenecking the CPU, or you're using a low-end SX and may as well just build a 386.

My fambly got a VLB based 486 SX33 in 93 - a “cheap” clone from one of those dodgy fly by night stores way out in the suburbs; still thousands of dollars. It was the hottest system amount my circle of friends, briefly.

VLB was pretty standard in North America on 486 machines made after 1992. VLB is really 1993 technology. I think it came out right at the end of 1992...like in November or December, and it was a pretty big deal. Even prior to VLB, not all 486s were purely ISA. Many OEMs had their own proprietary local buses, and EISA and MCA was available with the 486 at introduction.

My 486-33 was ISA only, and it was pretty decent with graphics until you wanted to go beyond 800x600 at 256 colours, which only ever happened in Windows. By the time software could actually take advantage of better graphics, you would have wanted a Pentium anyway.