PC slumming

Last Updated on September 30, 2010 by Dave Farquhar

Slumming. I spent a portion of the day Saturday messing around with an old 486-133. The DCE at church asked me what it would take to build an intranet. I said an old PC. So he handed me an old 486-133. I can’t shake this machine. I built this computer back in 1994 or so for a law firm. I performed several upgrades on it, including the 133 MHz upgrade (it started out as either a 33 or a 66, not sure which). Three years ago or so, when it was obsolete, the firm called me and asked me to haul it away. I asked my church if they wanted it. They did.
This 486-133 is available because it lost its old job to an old Pentium-200 I scrounged up and rebuilt. Trying to run anything more than a simple fileserver is pushing the limits of this machine. But I like pushing the limits. So I decided to see what I could do with it. I took it home and opened it up. Hmm, It had a 72-pin and 4 30-pin SIMM sockets free. I tried out an old 8-meg SIMM I had. It didn’t like it. I thought I remembered seeing some old 30-pin SIMMs laying around…. I found some. I put them in. It counted to 20. Nice.

I tried out a 420-meg HD I’d salvaged from somewhere or another. The system detected it as an 850. Curious. I disconnected the true-blue 850 in the box. It still detected the 420 as an 850. Mislabeled, perhaps? I’ve seen stranger things. So I started to install Linux. I was able to partition the drive, but then it emitted a click-o’-death when Debian tried to initialize the swap partition. So I did what I should have done in the first place. I took off the cover. Next time someone asks me how a hard drive works, I’ll be able to show them. So the 850 flew solo.

Then I added the last from a stash of old DEC Etherworks 3 NICs I had (one of my employer’s clients handed me a bag of them months ago and said, “Donate them to your cause.” I’ve been giving them away one by one ever since) and installed Debian 2.2. Debian installed a lot slower than it does on a Pentium.

I installed Squishdot. I found it could be tweaked to give a very professional look. I also found it horribly confusing because it’s so unlike any other content management tool I’ve used. I messed around with it for a long while, but it was slow. Really slow.

I tried some alternative kernels. No improvement to speak of. I added the noatime parameter to the root partition’s entry in /etc/fstab. That helped a little.

But still, it was swapping out and the CPU was topping out as well. The homepage was taking 18 seconds to load. That’s not good.

Apache serves up static Web pages just fine–no slower than any other computer. But this dynamic stuff might just be too much.

So as a last resort, I compiled a lo-fat kernel. I took 2.2.19 and basically answered no to all but the absolute essentials. Mouse? Forget it. I was half-tempted to leave out floppy support, but that would make maintenance a bit more difficult.

It’s unfortunate that I don’t have any matching pairs of SIMMs laying around. Otherwise I’d swap the board out for a Pentium-75. I’ve got a couple of ancient Socket 5 boards laying around, and at least one Pentium-75 CPU. I’ve got two mismatched 4s, but that’s asking for instability, and I’m not sure if a P75 with 8 megs is any improvement over a 486-133 with 20.

Compiles take a couple of hours. I really should have just compiled a .deb package on a faster machine and moved it over. It seems hard to believe that it wasn’t terribly long ago that a 486 was a perfectly workable computer, and now it feels like a PC/XT. But the 486’s heyday was 10 years ago now. And 20 years ago, the PC/XT wasn’t on the market yet, though its direct ancestor, the IBM PC, was. So I guess it’s not too unreasonable to regard this 486-133 as the Turbo XT of today.