The Resurrection of an 18 year old PC - the 486DX2 66Mhz

hamster

After comparing a Pentium 2 to a Pi, I started thinking about that old 486DX2 66Mhz chip on the mantelpiece. It was last in a PC back in 1993 and that was broken down for parts in 1995. I was thinking what if, just what if I could get that thing running again.

The Case: The case was still in one of the rooms, somehow a bird made a nest in it. It was covered in droppings and the case was missing.
Power Supply: The AT 180watt power supply was still in the case with the cables and the pc speaker magnet and ribbon.
Motherboard: The empty motherboard (made by SiS) was still in the case. 6 ISA slots and 2 Vesa Local Bus slots (extended ISA). No PCI slots in sight!
Memory: I had 8 sticks of 1mb simms(30x9) upstairs somewhere (the same ones that were ripped from it in 95). 2 sticks were stolen for a SoundBlaster 32 PnP.
Harddrive: The 240Mb Connor harddrive was no where to be seen. Thats ok, that 4.1Gb drive over there might do the trick. Think it was in a Pentium around '97.
Keyboard: Luckily I still had the keyboard as it uses a dplug connection. There is an old serial mouse with it.
Monitor: The Goldstar 15" monitor is not around anymore so I cheated using an old 15" LCD.
IDE Harddrive and Floppy drive controllers: The PC came with an ISA card. Looked like any soundcard - but what it did was house the IDE connectors & control logic for the hard drive and floppy drive.

Videocard:
The original video card, a Vesa Local Bus ISA video, with 1mb of Vram was in an old plastics Dunnes shopping bag with pins sticking through the plastic... might work says I. The beloved Tseng ET4000... Vesa Local Bus was before PCI or AGP or PCI Express standards came out. But was distinct from 16-bit ISA slots.

Soundcard:
The original one i had was an NX Galaxy Pro, an 8-bit "Soundblaster Compatible" card with ADLIB sound. This emulated SB fine but sometimes the cpu suffered.
A year later got a 16-bit Vibra 16 Soundcard (almost an exact SB clone) with a x3 CDROM reader (the caddy box tray kind). The motherboard has no IDE talking of. So the IDE connector was on the soundcard to connect the CDROM to the motherboard. The IDE controller on the soundcard emulated an matsumi cdrom. Which a Windows 98 boot disk in later years would actually detect. In this case dos drivers were supplied with the cdrom package.

Unfortunately, the soundcard I found was actually a Soundblaster 32 PnP designed for a plug and play bios when didnt really take off until 1996+. So no sound is possible for the moment but the pc speaker should do fine in games or utilities (not recommended).

This was a Reeves PC order from the UK, took a month to arrive and when it - it had to go back for a bios fix - the keyboard randomized keypresses - C would print Z and so on. This was an actual fault on the bios chip not the country region dos drivers.

What I did was:
1. Plugged in the CPU, slipped in the 8 sticks of ram. Put in the Power. Turn it on. 8 beeps. That means the cpu is ALIVE! It's ALIVE!
2. Brought down the LCD, slipped in the Tseng ET4000 vga card. Connected the vga cable. Turn it on. I see a bios flash up! 2 beeps. No Floppy or HDD which is expected.
3. Inserted the IDE controller card. Connected the floppy drive. Solid led light wrong way, flip around the cable still no joy. Tried a different card. Turn on - it finds the floppy drive!
4. Insert ms-dos 6.21 boot disk - it reads the disk upon bootup. No harddrive found obviously but works.
5. Rummage for a loose harddrive somewhere in the house. Ah 10Gb harddrive from 1998 - No Joy. Next a 4.1Gb drive from '97. Might work....
6. Boot up and ms-dos tells me I got a drive installed and would you like to install on it? Heck yes.. go for it! Whirrl Whirrrl...
7. I check the contents of the 4.1Gb drive... C:\Dos 5Mb installed, with config.sys, autobat.exec and command.com. Works.. with 241Mb free. I was expecting this..
8. Reboot fdisk (an old hard disk partition manager) tells me I have a 251 Hard disk installed. Ok......
9. Reboot - enter the Bios - under the hard drive - its entered as type 47 (well options from 1 to 46 gave different sizes). Type 47 is like user defined. You enter the number of Cylinders, Sectors etc and it calculated the drive. But this entry was for the old drive back in 1993. Its not auto detected or sized. So enforces the old size on the new drive.
10. I google the serial online and find the geometrics for the new drive. Now the bios says 4170Mb. Great, now lets format it.
11. Reboot. Fdisk tells me i have... 478Mb total when given a primary partitioned. Then I remember LBA... Large Block Addressing overcame the 501Mb limit.
12. This Pc does not support LBA. That's it a max of 478Mb on this. No Matter, it's still better than 248Mb which it had day one. It now nearly rivals the size of a CDROM disk.
13. Install Dos 6.2.1. It all works. Install Doom, works, Install Fractint for floating point unit work - works fine. Might install windows and see.

The CPU is quite hot and never had the basics of a mere heatsink. I would think it be more stable if it did. It did freeze rarely back then. But to think that I'd get this working after 18 years is amazing. A clock doubled 486DX2 66Mhz on a 33Mhz bus. With DosBox and an archive of 18,000 dos applications and games - might try a few benchmarks on it.

Alternatively perhaps a version of FreeBSD would work on 8Mb ram and install on 400Mb. No network and on an ISA architecture would be hard pressed to find such a card and even then the bandwidth would'nt be able to travel along the ISA bus.

When I was googling for drivers I saw this post on Vogons and my breath was taken away - Someone had done the same in 2010. The screenshots are very good, Board, memory (much clearer to see - the white banks of 8 rows). A smaller version of my ET4000 Tseng videocard, the onboard removable 256K cache on the motherboard. The same type 47 user set on the bios screen for the hard drive he had. He has a SoundBlaster Pro card so he'll have sound with the cdrom able to piggy back to the motherboard bus. The screenshots also show you can indeed install a 386SX or DX with/out a co-processor as well on the motherboard.


In screenshots I did the following:

The PC booting up with floppy and in the process of seeing if the harddrive is dead/alive or recognised. Notice the date on the soldered bios battery. It is still working after that length of time. Although when I turned it on - it was slowly losing track of time - 2000 instead of 2012, but still better than 1993. Set now and its fine.



A simple screen shot of the bootup screen when the floppy, harddisk and dos installed and then rebooted. American MegaTrends Intern (AMI) is the bios dated from 1992. The memory is 8Mb and im sure some of you know about the 640Kb conventional memory barrier where a program had to start and then access the memory beyond 1Mb either as extended or expanded memory (EMM386 was a driver that emulated such memory). Memaker works as does Defrag and Chkdsk from the prompt. It really does feel like a primative version of linux now. The help was there typing: help memmaker or whatever you wanted to read.
But to see the letters 80486DX2 again is just... magic!


There is the 1st bios screen - simply with the user defined entry (47) for the 4.1Gb drive i found - Note the bios calculates the size right but the bios can't allocate more beyond the 501Mb limit (which is LBA large Block Addressing issue - which was extended shortly before Windows 95 came along). It's also FAT16 which means you can only have 65536 files on the system. I did a bare check on the Raspberry Pi to see what a bare minimum install did (and i mean before anything) and it still installed 25k files. My Ubuntu system has 251k files. You could get around that limit partitioning the drives in separate drives with 65k files on each etc. But you still had an issue with slack space (where by a 1k file would still eat a 4k cluster, or a 5k file would eat 2 4k clusters (boxes)) FAT32 expanded this, NTFS gave security and now with ext3, ext4 etc we are spoiled for choice. File naming was limited in max length by: 12345678.123


This is inside the PC case. The long card on the left is the video card (Tseng ET4000 1mb). Notice the slot is longer than shorter slots. Thats is vesa local bus. There are 2 on the system here. The 2nd card is the IDE connectors/controllers allowing the hard drive and floppy to connect and be detected. Sadly there is no soundcard in one of the other slots. The 486DX2 is the chip near the ribbons (its name is upside down here). The pc speaker magnet can be seen botton middle attached to the harddrive case. In the middle you probably can see three sticks of ram (8 there in total), in the middle of those ide grey cables in white long sockets. The empty socket is where a 386 would go.




Finally with the case back on and cleaned (still need the 5.1/4 bay covers). I installed and tested a few items. Doom was always a good dos "application" to stress the cpu and video. Right now the chip is rather hot. 20fps doom - well maybe.. I'll have to benchmark it.

Khannie

Wow.

Lundar.

simply amazing

bonzodog2

Well done and nice pics. I found one of those CPUs in a box the other day, they fetch a lot more than a P4 on ebay, probably for scrap gold content. One job lot of mixed P4s(qty:16) sold for 16euro recently.

Anybody want a 386 laptop ?

Mincork

Firstly WOW , Great Job . I think it was one of those that got me into IT , I broke ( it broke while I was playing games on it ) a friends one and obviously had to pay for repairs , it took ya man about four hours and roughly €120 to repair it, needless to say , I chose that experience as a career move.lol

Rascasse

I'm surprised it still works after all these years. My first PC, an IBM Aptiva, had almost the exact same specs. Wish my mother hadn't thrown it in a skip 10 years ago.

Rambo

Good one
I had a pc like that , could not set date passed 2000 in the bios
it would just go back to 1980

Torqay

hamster wrote: »

Might install windows and see.

Alternatively perhaps a version of FreeBSD would work on 8Mb ram and install on 400Mb.

OS/2 Warp FTW!

Grand job btw.

jesus_thats_gre

The boot up screen has me lusting after my old Digital DX2 66... To this day, I am proud of getting Need for Speed running with 4megs of RAM

ED E

My uncle has about 20 such boxes sitting in his basement. Pity he's in the states or I'd have some fun. Would probably fail hard though considering I'm too young to remember past win95.

Khannie

I ran the server for my final year project on a similarly spec'd box. Bought it second hand for next to nothing. Had it running linux (command line only). It had a web server, database and various other bits running on it and was still very nippy.

hamster

Thanks for the comments. I didn't expect this so soon but I got a hold of a Vibra 16 ISA card!! It was living in a PentiumII-266Mhz that I still have (it has shared ISA and PCI sockets so that was fantastic).

This soundcard has 3 IDE connectors: Standard IDE, another for Panasonic and a Matumi one according to the print on the pcb.


Next, I booted up and extracted 3 floppies of SB16 drivers (downloaded the night before) into a directory and ran install. The installer picked up the right settings 1st time. The classic 220H, IRQ: 5 and DMA:1. The high DMA for 16bit sound and 330 for music. Lines added the config.sys and autoexec.bat.


With the soundcard working, I plugged in the cdrom. This is a 12x LG from 2000, bent the 10th IDE column pin on the soundcard (counting from the right side from pin1) to get the IDE connector on.

From the screen you can see 3 cards installed - The Vibra16 is the greener one in the middle with the IDE cable plugged into it at the end of the card. You can see two columns of IDE pins for the earlier matsumi and Panasonic cdrom drives.


Rebooted with a windows98 floppy and a couple of ISA/PCI scans later it finds the cdrom. Fantastic.


I decided to test the sound with an old PC Format Cdrom (the 4th cd edition they released). It has a ton of old mod music files, avi Mandelbrot zooms using fractint and some doom levels.

CD MODS
WOWII AFRIKA.MOD


How the case internals now look with the soundcard and cdrom in.


Next it's possible to get an 8 euro ISA ethernet card and maybe connect to the network and try DosLynx web browser. Although with 8Mb it will be a challenge. This pc did run Encarta '94 and the famous Berlin Wall clip without falling over. In windows it did use 800x600 in 32K color thanks to the Tseng ET4000.

Having said all that - there are few issues to sort out. The motherboard where the D plug for the keyboard goes in has a dry joint fault on the board. That is, I notice occasionally on boot up - the keyboard can fail. Sometimes its a HDD controller failure and lastly the Cdrom data connect went after 10minutes AFK (although power-wise it was fine). A bit of soldering under the should fix that. But I'll have to take out the motherboard for that. So for now I'll leave it. But that's pretty much where it was in 1994 - that summer got the 16 bit soundcard and x3 cdrom. The year before it was just the floppy and harddisk. Restoration Job complete!

old_aussie

Even runs without a CPU heatsink, wow.

dazberry

hamster wrote: »

When I was googling for drivers I saw this post on Vogons and my breath was taken away - Someone had done the same in 2010. The screenshots are very good, Board, memory (much clearer to see - the white banks of 8 rows).

Thanks for the link. I had a 386DX-40 back in the early 90s, and got all nostalgic a while back and started looking to rebuild one. Original board I had was similar to the one pictured. Mine was hacked together from bits and pieces 'cos I had no money and I remember it benching the same as one of the guys new IBM 486s

D.

Torqay

hamster wrote: »

Next it's possible to get an 8 euro ISA ethernet card and maybe connect to the network and try DosLynx web browser. Although with 8Mb it will be a challenge.

If you really want to browse the web with this baby, see if you can get your hands on OS/2 Warp 3. IBM's WebExplorer still works with many websites. Netscape/Warpzilla with Java and Flash is probably a bridge too far with only 8 meg.

Warp certainly beats the hell out of Windows 3.x

Tea_Bag

What a fantastic resurrection.

A++

Alun

Great thread! Tseng Labs ET 4000 ... now that brings back memories!! The first PC I ever built was even older than that, a 80286 system complete with a fully stuffed Intel AboveBoard, plus SCSI hard disk and CD-ROM as I didn't trust that new fangled ATA stuff. I still have the Adaptec 1542B SCSI controller if you or anyone else is interested by the way. Stupidly I threw out a bunch of old network cards just a few months ago, including a classic NE2000 clone that would have been perfect for this. Had a 386SX and a 486DX2 system too later on.

Alun

I should add that I've got a bunch of ancient software on floppies still if you're interested ...

Netware 3.11, PC-NFS, PC/TCP for DOS, QEMM 386, Desqview/X, Windows 3.1, Several DOS versions, MS Office (4.2 I think), PC Tools for Windows, Norton Utilities, etc.

I don't even know if the floppies are still readable, but you're welcome to them if you want to give them a good home

SirLemonhead

Alun wrote: »

I should add that I've got a bunch of ancient software on floppies still if you're interested ...

Netware 3.11, PC-NFS, PC/TCP for DOS, QEMM 386, Desqview/X, Windows 3.1, Several DOS versions, MS Office (4.2 I think), PC Tools for Windows, Norton Utilities, etc.

I don't even know if the floppies are still readable, but you're welcome to them if you want to give them a good home

I would myself if the OP doesn't want em I've got quite a few old pcs

I've recently "resurrected" an old Dell 386 that just turned 20 years old in June :pac:

The battery in it had leaked (it actually went all..furry too) so that had to be all cleaned up, but fortunately didn't cause any major issues.

Here's the battery:


And the damage it did, after a bit of a cleanup:
https://dl.dropbox.com/u/30279551/20120227_210943.jpg

So if anyone has any really old pcs in storage, it'd be a good idea to remove the battery if you haven't already..

And the machine itself:


There's a Parallel Zip 100 drive to the right of the Xbox 360 that's REALLY handy for transferring files (I have a USB zip drive for my modern pc)

It's got a network card in it but I haven't set that up yet. I have a load of classic point and click adventure games on it at the moment. Doom never did run so well on it

Alun

SirLemonhead wrote: »

I would myself if the OP doesn't want em I've got quite a few old pcs

I've recently "resurrected" an old Dell 386 that just turned 20 years old in June :pac:

The battery in it had leaked (it actually went all..furry too) so that had to be all cleaned up, but fortunately didn't cause any major issues.

No problem, if the OP doesn't chime in you can have them!

Backup batteries are a real pain in old PC's. They're often soldered in as well, but luckily some have a 2-pin header that you can attach an external battery to, which I've done on an old Compaq server I have that's also probably 20 years old too

SirLemonhead

old_aussie wrote: »

Even runs without a CPU heatsink, wow.

All the old pcs like that didn't have anything on the CPUs at all :pac:

SirLemonhead

Alun wrote: »

No problem, if the OP doesn't chime in you can have them!

Backup batteries are a real pain in old PC's. They're often soldered in as well, but luckily some have a 2-pin header that you can attach an external battery to, which I've done on an old Compaq server I have that's also probably 20 years old too

Yeah i'll get around to eventually changing the battery. It should work ok if I link up 3x 1.5volt batteries. I have to manually configure the bios every time I turn it on but it's no big deal.

If you've got several versions of Windows 3.x and Dos, If the OP wanted to take the "best" versions i'd appreciate anything at all I can get my hands on leftover

Alun

My Compaq runs just fine on 2xAA, so only 3V, but the original battery was a 3V coin cell. You can easily buy AA battery holders with 2 places, and I think 4, not sure if you can get one's with just 3.

If you want old versions of DOS, I've got image files (for WinImage) of pretty much everything from DOS 1.0 onwards, and Windows too from 1.0 onwards. I downloaded them from somewhere on the net, I can't remember where now. I've even got some of them working under VMWare for a laugh

I think the only version of Windows I have on diskette is 3.1, i.e. not Windows for Workgroups 3.11, but I'll have to dust off (literally!) the diskette boxes and check.

EDITY: sorry, can't find the ancient DOS versions at the moment, I'll have to go searching

SirLemonhead

I have a few things as disk images but I really love the idea of owning the genuine disks I collect a lot of old pc stuff..have a decent bit of hardware but not a lot of original OS disks unfortunately!

Alun

OK, I'll have a look tomorrow and see what I've got and report back.

Torqay

SirLemonhead wrote: »

All the old pcs like that didn't have anything on the CPUs at all :pac:

That's actually not true, you could get heat sinks and even fans for the 486dx2. They were usually sold extra and certainly recommended if you wanted to overclock this baby. The dx2-66 easily ran at 80 MHz, most boards allowed for this because the AMD and Cyrix 486dx2-80 required higher clock speeds (back then, Intel, AMD and Cyrix processors all fit the same CPU socket).

SirLemonhead

Torqay wrote: »

That's actually not true, you could get heat sinks and even fans for the 486dx2. They were usually sold extra and certainly recommended if you wanted to overclock this baby. The dx2-66 easily ran at 80 MHz, most boards allowed for this because the AMD and Cyrix 486dx2-80 required higher clock speeds (back then, Intel, AMD and Cyrix processors all fit the same CPU socket).

So you're saying they generally came without heatsink and fan? :pac:

I didn't mean ALL I guess, mostly a lot. Mine certainally didn't but I did have a 486 that had a heatsink now that I think about it

Alun

Ah Cyrix, whatever happened to Cyrix?

Torqay

Alun wrote: »

Ah Cyrix, whatever happened to Cyrix?

Merged with National Semiconductors in 1997 and was sold in 1999 to Taiwanese chip makers VIA Technologies.

Torqay

SirLemonhead wrote: »

I have a few things as disk images but I really love the idea of owning the genuine disks

You'd have to be extremely lucky to find 20 year old floppy disks that are still working, they're way past their sell-by date by now.

Torqay

hamster wrote: »

There is the 1st bios screen - simply with the user defined entry (47) for the 4.1Gb drive i found - Note the bios calculates the size right but the bios can't allocate more beyond the 501Mb limit (which is LBA large Block Addressing issue - which was extended shortly before Windows 95 came along). It's also FAT16 which means you can only have 65536 files on the system.

If you can hunt down MS-DOS 7.1, you'll have LBA & FAT32 support. In order to run Windows 3.11 on DOS 7.1, you'll need 3xstart.exe (download here). This program will modify IO.SYS to make it compatible with Windows 3.x