Installing FreeDOS on a 486

I wish I had more time for retro computers. Since my last post, I've been building 486DX2/66 system using spare parts I already have. When it is complete, I plan to try to sell it in Finnish auction site called huuto.net. To be honest, I don't actually expect anyone to buy it from there, at least not with the price I'm thinking of (it is going to be very nice system). I've never sold anything on ebay so maybe it is time to try although I fear postage might scare potential buyers off.

I'll tell more about the system when it is complete (and all the problems I've faced so far) but it is going to have a microdrive (I prefer those over CF cards) for easy and fast way to transfer files between it and modern system. So the system is going to have XTIDE Universal BIOS in it and I also plan to install DOS and old commercial games that are now released as freeware along with popular shareware games.

Since I'm going to sell the system, I just can't install any DOS no matter how old they are now. I would have liked to install PC DOS 2000 (100% compatible with MS-DOS 6.22 but more optimized with extra features) but the only option now is FreeDOS since it can be distributed free. I'm installing version 1.1 that is the latest.

I've been testing XTIDE Universal BIOS with FreeDOS boot disks but I've never installed whole FreeDOS. For those that do not know, FreeDOS is meant for more modern systems and so it may not be a perfect choice for retro gaming. There is 8088/8086 compatible kernel so it can be used even on oldest PCs but you'll likely need to customize your own version for 16 bit systems. There might be unexpected problems. For example I was able to boot my 286 with FreeDOS boot disk but it always froze when I tried to boot from hard drive. I was able to make 486 system bootable with the very same boot disk without any problems.

For retro gaming purposes FreeDOS has one great benefit over PC DOS 2000: FAT32 support. You won't need it unless you use out of era hard disks (I have 120 GB drive on my 286) but if you do, you'll no doubt want to access more than 8 GB and don't want to be limited to 2 GB FAT16 partitions.

MS-DOS 7 (Windows 9x) has FAT32 support but MS-DOS 7 requires 386 or better. PC DOS 7.10 works on 16-bit systems and also supports FAT32 but 7.10 is only available as boot disks. I found a collection of PC DOS 7.10 boot disks (different builds) and tried to install them over PC DOS 2000. It worked but every build had the very same problem: himem.sys consumed lots of conventional memory, many times more that it did with PC DOS 2000.

I eventually came to the conclusion that FAT32 is not that important for XT and 286 systems and I'm going to replace the 120 GB drive from my 286 system next time I open it. For 386 and later you can choose between MS-DOS 7 and FreeDOS and I recommend to at least try FreeDOS.

But for the 486DX2 system I'm building it was damn hard to install using official CD image for the FreeDOS 1.1 distribution. The CD is bootable but this old 486 does not support boot from CD-ROM. The CD contains setup.bat so booting from CD should not be needed. Well, the setup froze when I used MS-DOS 6.22 boot disk. Setup also failed with the FreeDOS boot disk I already had. All I got was out of environment space errors. I had to examine install documentation to find that setup requires 2k environment space to be set.

FreeDOS installed perfectly on my Pentium system (that was able to boot from CD). I tried to create install boot disk using it but it did not work much better. There was always something preventing the install. Finally I used the Pentium system to install FreeDOS and then moved the microdrive back to the 486.