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286/386/486 Demoscene

category: general [glöplog]
heh, i bought a i486DX2-66 in 1994, kept being my "retro" pc till a few years ago for running old demos/games. later also added a 3dfx voodoo in there.
Yes, should be the gfx card. I got this Amstrad ALT 286 yesterday with 8bit ISA Cirrus Logic, 20fps at max no matter if it's rep stosb or stosw. Games like Lotus 3 or Wolfenstein 3D where very slow and I thought at first that maybe you need a 386 for proper speed. But then I watched them really smooth on this video http://www.youtube.com/watch?v=S_ZEWvokp3o

And it's impressive what kind of great 2d/3d games that 286 could run smoothly. With a proper Tseng Labs of course.

Still, Legend of Impact studios in this machine ran full frame rate at most parts, only a bit slow on polygon parts. And a lot of older demos where cool too.
added on the 2014-02-10 12:03:13 by Optimus Optimus
Quote:
heh, i bought a i486DX2-66 in 1994, kept being my "retro" pc till a few years ago for running old demos/games. later also added a 3dfx voodoo in there.


yeah i had a voodoo based orchid righteous 3d around 96/97.. it was about £280, my first cdrom drive (4 speed!) for that PC was £120.

my biggest regret is swapping my amiga 500 for a megadrive with stacks of games (i had a cd32 which i still have)
added on the 2014-02-10 12:20:02 by Canopy Canopy
it was an expensive hobby indeed. and still is if you wanna have a highend system for doing 3D graphics ;)
I used to have different main boards and CPU back in the day, 286, 386sx, 386dx 40mhz, 486dx 44mhz and Pentium 60mhz. I used to switch them almost every week just for fun but then I burned my 386dx when cables stuck in the fan and it overheated.
Secret of monkey island, another world, gods were quite fast on 286 but
Wolfestain 3d wasnt smooth. It used to skip frames.

It was also painful to run some of demos on 286 back in mid 90s.
Holistic by Cascada crapped during the Porshe 3d scene.
Stars by Noon didn't work at all :]
added on the 2014-02-10 20:34:08 by Forcer Forcer
I had a 286 too, and yes, it was noticeably faster than the 386SXes some friends had (all at 16 MHz). Actually that's not surprising at all, because the (32-bit) 386SX was massively wasting bus cycles due to its crippled (16-bit) data bus, just like the 16-bit 8088 did due to its 8-bit bus.
added on the 2014-02-11 09:48:33 by KeyJ KeyJ
Yep, but maybe there is a loss only when using 32bit regs? So, a game coded for 286 would be the same or faster or slower?

I have seen here some opcodes have sometimes less cycles on 286 than 386/486. But most of the standard ones are the same or less on 386 or later. I still believe it must be gfx card or something.
added on the 2014-02-11 12:55:36 by Optimus Optimus
Are this cycles ok? Or should I also add the type to fetch and interpreter the opcodes from memory? I am curious, I am counting cycles per pixel and stuff but of course they won't be precise. I will read Abrash's book to know more about. Maybe 286 or 8086 it is easier to count cycles and take only few other things in account. Is there a rule that if an instruction is 3 bytes then it's 3xN additional cycles wasted?
added on the 2014-02-11 13:01:32 by Optimus Optimus
Optimus: Unfortunately, it isn't that easy.
The core of a 386 (*any* 386, both SX and DX) is full 32 bits wide, including the BIU ("Bus Interface Unit"). This means that the 386 will always read and write memory in 32-bit words, which is then split up into two 16-bit accesses in the SX. That's perfectly fine when actually performing a 32-bit memory operation; you can't get any faster than that with a 16-bit data bus. However, if the code is doing a 8- or 16-bit operation, this will be "amplified" into *two* bus cycles. It's the same as with the 8088, which was a 16-bit CPU with an 8-bit bus.
Regarding those cycle counts, remember that they don't account for instruction fetches and memory wait states, let alone the 8088 and 386SX's amplification effects.
And yes, Abrash's book is a really good read if you're interested in these (semi-archeological) details :)
added on the 2014-02-11 15:35:03 by KeyJ KeyJ
Oh, I now get it. Of course. I am wondering if PcEM emulates this difference.
added on the 2014-02-11 18:35:02 by Optimus Optimus
And I will check TopBench database also.
added on the 2014-02-11 18:35:18 by Optimus Optimus
Just stick to 6502, easy to count cycles ;)
added on the 2014-02-12 12:06:34 by Scali Scali
Z80 ftw!
added on the 2014-02-12 12:57:01 by Optimus Optimus
Are there any Demos that will run with an EGA-Graphics-Card, or is this the only one ?

https://www.pouet.net/prod.php?which=3972
There are many other PC demos in ega although some of them might have been flagged as non-working because of on-board faulty chip emulation by motherboard manufacturers who only implemented the vanilla minimal whilst everybody was looking the other way at gpu. Same goes for soundblasters OPLx standards. The demo you are referring to had the chance to gain initial attention to be recorded and put online.
Can't recall much EGA stuff from the DOS days. CGA or textmode, yes. Some older Ultraforce stuff is probably EGA and then there was some slideshow with Garfield pics.
added on the 2014-02-25 20:58:36 by Marq Marq
Spdemo1

I also have some disks with EGA-demos that I haven't found on the internet yet, will probably upload them somewhere at some point :)
added on the 2014-02-26 07:02:04 by britelite britelite
Yebo also features some EGA-magic
added on the 2014-02-26 07:05:33 by britelite britelite
Happy Birthday, Rebel Fun and Space Fun are also in EGA.
added on the 2014-02-26 07:08:34 by britelite britelite
You sure Yebo is EGA? The colors don't look like it...
added on the 2014-02-26 10:00:48 by Marq Marq
Yey, Mega Ega. Ran nicely on the 286.

Yesterday I got a sound blaster 8bit. Plays nicely for some demos but usually you have to give very low khz so that even the sound plays fast enough. I am curious about the CPU time wasted and which are the fastest players released. An alternative is adlib, which I really like the nostalgic sound of it, I may consider this one (or mixed with sampled sounds) if I code a demo for the 286 (I currently continue working on my 386dx/486sx demo, next will be the 286 with this slow gfx card, the challenge :)
added on the 2014-02-26 11:15:15 by Optimus Optimus
Marq: it shows a different part with EGA
added on the 2014-02-26 11:16:31 by britelite britelite
I also recall seeing an EGA megademo by some classic amigagroup, probably scoopex or trsi. Can't seem to find the demo anywhere anymore :(
added on the 2014-02-26 11:18:35 by britelite britelite
Oh, and Future Crew also did some EGA-stuff, like Gr8 :)
added on the 2014-02-26 11:20:20 by britelite britelite

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