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Its historical context.

>ISA was not an option for VIDEO card at early 90s.

Not sure what you mean when >99% of all Video cards shipped in 1990 were ISA. Alternative were just released EISA and failed MCA. Do you mean not viable performance wise? I dont see how ISA capable of ~5MB/s write speed is a bottleneck when updating 320x200@60 takes less than 4MB/s. Even ignoring fancy ISA 2D video accelerators like 8514 or TIGA, here is this https://github.com/mills32/Little-Game-Engine-for-VGA-EGA running on 8MHz 8088 XT equipped with ordinary ISA VGA https://www.youtube.com/watch?v=t98OKbYonQI&t=273 @11:10 shows Turbo off 4.7MHz.

>VESA (VLB) was not an option, because it was LOCAL bus, closely tied to CPU architecture, so 486 VLB was not compatible with machines with ANY other CPUs

https://amiga.resource.cx/exp/egs28 https://amiga.resource.cx/exp/piccolo https://amiga.resource.cx/exp/piccolosd64



You comparing apples with carrots. In democracy you sure have rights for such comparing but I have rights to say you are wrong.

> I dont see how ISA capable of ~5MB/s write speed is a bottleneck when updating 320x200@60 takes less than 4MB/s

This is because you have not learned theory of https://en.wikipedia.org/wiki/Queueing_theory

This theory said, to have sustained performance of Y you must have capacity at least 4*Y (and in cases of small systems could be not 4 but 10 or even more).

If you don't have free capacity, you will periodically suffer bottlenecks.

When Amiga appear, it does not have bottlenecks, it was perfect balanced machine for that time. When appear 386 and even 486, and corresponding 68k CPUs, the more and more architecture become bottleneck, but it was not very obvious. But after started shipping of Pentium machines and drop prices on RAM, so 2M or more become affordable, and people seen 700p screen resolution, it was just too late.

> https://amiga.resource.cx/exp/piccolosd64

They said about Zorro III 32-bit bus, which is not ISA, if you cannot see such obvious thing yourself.


> you must have capacity at least 4*Y

with x4 in theory ISA VGA could never produce more than ~19fps

How do you explain Doom running at 32fps https://thandor.net/benchmarks.php/vga/vga?a=69&c=0&o=0&s=Su...

and again this https://github.com/mills32/Little-Game-Engine-for-VGA-EGA does vsync locked 70fps full screen scrolling on 286 with VGA, and 35fps on 8MHz XT.

>They said about Zorro III 32-bit bus, which is not ISA, if you cannot see such obvious thing yourself.

https://www.vgamuseum.info/index.php/component/k2/item/141-c...

"GD5434 Bus:ISA 16bit, VL-Bus, PCI"

I dont see Zorro in the supported Bus type. VL-Bus is not some special custom Intel 486 CPU bus, its a name for an industry standardized way of attaching memory mapped peripherals. There are even 386SX motherboards with _16bit_ VL-Bus slot https://theretroweb.com/motherboards/s/alaris-leopard-486slc...


Well, I seen many times, when one people lie to other people. You are very special case, you lie to yourself. Sure, in democracy you have right to do so, as you wish.


Are the benchmarks I listed faked? Is there some ISA VGA conspiracy Im not aware of?

Please find old XT/286 computer with VGA card and run https://github.com/mills32/Little-Game-Engine-for-VGA-EGA, its free.


Your words so novice, and you make huge number of mistakes, so I need spend much resources to talk with you. And I have no feeling, you value my time.

Please answer question(s): why these efforts valuable for me? Or why these efforts valuable for Amiga community?


I dont know what your deal is. You state things that are undeniably not true (ISA not an option), then call me a liar when faced with evidence to the opposite.

> In democracy you sure have rights for such comparing

the what now? This isnt going anywhere productive :)




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