Modern OS for an Old PC: a dumpster Pentium I story

I recently came across an old machine resting on top of a dumpster just as it started to rain. Feeling a bit sad for it, I decided to give this computer a second chance. To my surprise, it turned out to be a 1st generation Pentium running at 200 MHz with 256 MB of RAM—quite impressive for its time back in 1997!

Hardware

The motherboard is a Socket 7 Lucky Star 5I-TX1 REV 2.0. The computer came with two USB ports, but it cannot boot from them. Only HDD, CD, and 3.5" floppy drives are supported.

Memory tested OK but unfortunately, the hard drive was dead, it was making a chirping noise, reminiscent of a bird. I pulled it out and now I'm waiting for an IDE to SD card adapter to arrive, which will help breathe new life into this vintage machine.

PCI 56K Software modem with Motorola chip 62412-51. I don't think we'll be needing it.

The computer came with a PCI 56K software modem featuring a Motorola chip, model 62412-51. Those PCI cards sell for $20-$25 USD on eBay, though I am not sure if this one works - at this time, I won't bother testing it. Since I can not find any use for the 56K modem, I replaced the card with a spare network card. 

HDD and CMOS battery dead

Not to my surprise, the CMOS battery was dead. The new battery didn’t fit properly, likely due to deformation of the slot over the years. This caused a loss of contact, resulting in the BIOS losing its settings every time the power was disconnected. To fix this, I placed a layer of aluminum foil under the battery.

With that issue resolved, it was time to attempt running a live distribution on the machine!

Operating systems 

I am interested only in up-to-date, maintained operating systems that can run on a machine that old. The computer will be connected to a home network with access to the internet, so any old and unmaintained operating system could present a security threat.  

FreeDOS 

FreeDOS 1.4 running on a dumpster Pentium I

FreeDOS was my first choice to try out, and it didn't fail me! The LiveCD booted without any problems, and I was able to try out some applications and games. However, it's frustrating that some games and applications are looking for a swap file on the C drive (which I still don't have), while the memory-mapped drive is on the R drive. Additionally, it would be nice if it detected a network card. Configuring the network card requires saving configuration files and rebooting, which obviously doesn't work on a LiveCD.

antiX 

antiX [wikipedia article] was next on the list. Though it is claimed that it is "suitable for older, less powerful x86-based systems", it turned out that my system is too old for it. 

antiX initial boot screen

The antiX documentation states that the recommended minimum memory is 512MB, while my machine has only 256MB. According to the same documentation, that should be enough for antiX-core (v26, 32-bit), which I tried to run (as I am interested in a console OS only anyway). 

The first problem during the boot was an ‘ACPI BIOS error’ which I solved by adding acpi=off to the boot line. However, I couldn’t get past the next problem — kernel panic.

antiX kernel panic on Pentium I

init was trying to execute an instruction that is not available on the i586 architecture. The telltale signal was the exc_invalid_op message and code <0f> 43, which corresponds to the CMOVAE instruction introduced with the P6 architecture. It turned out that although the kernel is compiled for i486, init is not, and support for those machines has been dropped. You can see the full thread on the antiX forum here. Time to move on...

NetBSD 

NetBSD is available for a wide range of platforms, and my old one should be included. The i386 port wiki page states that "any i486 or better CPU should work". I created a bootable CD from the NetBSD-10.1-i386.iso image and tried to boot the machine. However, during the boot process, NetBSD displayed only the following:

NetBSD/x86 cd9660 Primary Bootstrap

and everything stopped there. Not a single character more. Next, I tried to 'force' the boot from USB via Plop Boot Manager, which is a great tool, by the way! Now, I got the following displayed:

NetBSD MBR boot

NetBSD/x86 ffsv1 Primary Bootstrap

... and then everything stops just like with CD. The same happened with NetBSD versions 9.4 and 8.3. Obviously, the boot procedure is stuck either in the transition from phase 1 to phase 2 or in phase 2. The same thing happened after the BIOS was patched. Being out of ideas, I will leave this here for the moment.

Tiny Core Linux

I created a live CD with the Core version, which offers only a command line interface. Tiny Core Linux booted in seconds, detected the network card right away and I was ready to download the files necessary to patch the BIOS.

Other operating systems

I successfully booted KolibriOS as well, which has a graphical interface by default. It was running slowly, it didn't detect my graphics card properly, so the resolution was rather low. Additionally, it seems that the OS doesn't support a mouse on the serial port. It also did not detect my network card.

Debian's last version working on i586/P5 is v8.11.1 (Jessie) from 2018.
Up to date Alpine Linux requires i686 compatible CPU or later.

Slackware might support my machine, and Gentoo too—if I decide to compile everything. I'll leave those experiments for some other time.

Patching the BIOS

The original Award BIOS that the machine came with has a bug that causes the system to hang if a hard disk drive larger than 32GB is detected. I found an unofficial patch here and downloaded it along with a FreeDOS floppy boot image and the Award BIOS flasher.

Using Tiny Core Linux to create a FreeDOS bootable floppy

Patching didn't go smoothly either, as the latest Award BIOS flasher (version 8.99) constantly displayed the message "The program file's part number does not match your system!". I read on a forum that this is actually a problem with the flasher, and that version 8.x does not work well with Socket 7 motherboards. Flasher version 7.95 worked fine, and now the BIOS is patched! Just in time for disk installation.

BIOS successfully patched!

To be continued ...