VOGONS


First post, by Ltsyrek

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Hi,
I would like to present you my new DOS machine. The aim of this build was to make strong multitool 486 with VLB cards and put as much nice stuff inside as it is possible 😀

How does it look:
Front:
UjRXI2R.jpg
Back (my, so many ports to tinker with...):
Y8CYdMq.jpg
The guts are really crowded 😀
EWVCPUd.jpg

What is inside?
Motherboard:
Chicony CH-471A, based on SiS 471 chipset, with 3 vlb and 5 ISA slots. In general, it is a very stable motherboard for wide range of 486 CPUs. It only accepts parity 72-pin SIMMs though, so expanding RAM is a bit more difficult. The motherboard is equipped with 256kb 15ns cache.
I removed the battery and now I' m using CR2032 in socket soldered to a cable connected to external battery. I also added a potentiometer to PC speaker so I can now change the volume of PC speaker sound.

CPU:
Zdj-cie0681.jpg
AMD 5x86 clocked at 160 Mhz (4x40). I am using a fan and a radiator to cool it a bit.

RAM:
64MB, in two 32MB 70ns modules made by Viking. It was so difficult to find cheap parity 72-pin SIMMS...

Graphics cards:
1. Mirocrystal 8S, based on S3 805 chipset and equipped with 2MB of 70ns RAM. The card contains switches that allow to change the horizontal frequency.

2. Winbond W86855AF, a hercules graphics card with 9pin TTL output and bonus LPT port.

Sound card: Sound Blaster 32 (CT3600) with 8MB of RAM added.

Network card: 3COM Etherlink III.

HDD controller:
PTI-255W/VL. Now, this one was hard to setup. With the right driver loaded, it allows to use 4 IDE devices at once. However, it was very picky about the drives used. It was not able to detect some drives, even those with low capacity (tested 40MB to 10GB). Also, some drives were incompatible with each other for some reason or the driver was not detecting them on secondary port. In addition, these IDE ports are not compatible with ATAPI, so the CD drive connected to it will be detected, but there will be MANY data corruption issues while accessing files on CDs. As a bonus, this card also gives two COM ports and one LPT port.
After trying many HDD combinations, i found one that was satisfying enough for me...

DRIVES:
Floppies - Generic 3,5", 1,44MB and 5,25", 1,2MB
Primary Master: Quantum Fireball EL2,5A, 2,4GB, split into two partitions - one for WfW 3.11 and DOS 6.22, and another for Windows 95. As a boot manager I am using GAG:
2oCzQZs.jpg
It does support many different languages and it is easy to setup from floppy.
Primary Slave: Transcend 1GB CF card; the CF card adapter is mounted in the back, by using a bracket - I am using it as a "pendrive" for copying files from my modern PC.
Secondary Master: Seagate ST33221A, 3GB, also split into two partitions - 1GB one for modules, music, demos and images, and 2 GB one for games. Despite being bigger than Quantum, it is slower, so I decided to use it as a storage drive, not a system one.
Tertiary Master: HL-DT-ST DVD-RAM drive. It was the only DVD writer I had, and I know it does not match with the builds' period correctness 😀 I didn' t test CD/DVD burning yet, though...
Bonus Drive: 16MB RAM drive, for TEMP variable and just because I have so much memory I don' t know how to use it under DOS. 😀
Also, I am using Smartdrv with 16MB buffer for all hard drives.

PERIPHERALS:
Monitor: LG Flatron F700B, not really period-correct, still it is working well and handles lower resolutions flawlessly. For tinkering with Hercules card, I am using an old IBM 5151.
Keyboard: Generic DIN keyboard.
Mouse: A4Tech Neo 702, just standard 2-button COM mouse.
Dual gameport adapter - AlfaData AlfaTwin - it allows me to use two gamepads/joysticks at once, very nice for multiplayer gaming. 😀
rnwNgDp.jpg
Gamepad: Genius MaxFire G-07 - very ergonomic and durable gameport gamepad.
Joystick: Tevion Erazer.

The whole setup:
7AINJOI.jpg?1
The Amiga 1200 is a bonus 😀 unfortunately I do not have enough space yet to set up everything without crowd.

Last edited by Ltsyrek on 2019-03-06, 21:04. Edited 2 times in total.

Reply 1 of 8, by treeman

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A very nice build! I also have a 5x86 build running at 160 but unfortunately pci, a 160mhz vlb is the ultimate goal but I ran out of steam.

I really like the potentiometer mod, excellent idea I may look into this too, I put foam over my pc speakers to quiet them down a bit.

I would be interested to see some benchmarks and a quake score to see where the VLB card puts the system

Reply 2 of 8, by Ltsyrek

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5x86 with PCI is also a great idea! In fact, I would like to have both VLB and PCI system just to have even more possibilities - in PCI system it is possible to use a Voodoo card, an USB controller and PS/2 mouse port, so it does have some advantages over a VLB build. 😀
As you wish, here are some benchmarks and photos:
SpeedSys (and comparison of drives):
Quantum Fireball EL2.5A:
icYRY6x.jpg
Transcend CD card:
mv53cGy.jpg
Seagate ST-33221A:
aGWQqqr.jpg

Quake - 14,9fps:
voUQnRr.jpg?1

Doom:
j5Lnxsh.jpg
(2134/1626)*35 = 45,9 fps.

PC-Config:
fFBP6h7.jpg

Everest for W95:
jVDGG36.jpg

Windows 95 desktop:
LskbSAg.jpg

WfW 3.11 desktop:
aGMZhPy.jpg

Browing Vogons using Dillo in DOS:
sIjjD7x.jpg

Hmm...
qEWCsZS.jpg

If you want some more benchmarks, I can post them tomorrow.

Reply 3 of 8, by Intel486dx33

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That's a good CPU (AZD) edition.
Did you try to overclock to 200mhz ?

Reply 4 of 8, by treeman

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some nice results, I got 15.2 fps on my 160amd running a 4mb pci s3

Reply 5 of 8, by Ltsyrek

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Intel486dx33 wrote:

That's a good CPU (AZD) edition.
Did you try to overclock to 200mhz ?

Yeah, I have tried setting the bus to 50mhz. Usually the PC does not even post, sometimes it detects CPU as 200 mhz and hangs soon after booting. I don' t see much sense in overclocking to 200mhz and setting wait states, perhaps there would be no speed difference.

treeman wrote:

some nice results, I got 15.2 fps on my 160amd running a 4mb pci s3

The CPU is a bottleneck in case of Quake. IIRC the only thing that makes Quake fluent in 486 is running GLQuake on PCI motherboard and Voodoo accelerator.
Still, 15 fps is "playable" 😀 the only DOS game that I found totally unplayable with that config is Carmageddon (even with lowest graphics settings!).
For the PC speaker volume mod, i simply added one 10 KOhm potentiometer in middle of one of the wires and mounted it on the front panel.

Reply 6 of 8, by treeman

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I usually just use quake for fps measure don't really play it, but 14-15fps is very respectable on a 486

did you try more voltage at 200mhz? I don't think stock 3.3V will be any good usually people do 4v and from reading about 586 apparently 4.6V is the tolerance threshold for a amd 586

I never wanted to push past 160 for cpu safety, I got a board with a crystal that can be changed, if there is a 45 mhz crystal I would try 180mhz at 4V... maybye I will look into this

Reply 7 of 8, by Ltsyrek

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Well, same here - 5x86 is relatively uncommon where I live, so I prefer to not strain it too much. I am running 5x86 at stock 3.45V and never tried to increase voltage, honestly.

Reply 8 of 8, by chinny22

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That's one full PC!
Bit late now but a recent build refused to work with all but 1 of my hard drives, all less the 8GB. Swapping from 80 pin to 40pin IDE cable worked fine.