In my family, we have 6 PCs, I don't remember if we ever had to throw one away. Probably we didn't. So anyway, the oldest PC is from the '98 era, I remember the days we had Win98SE there. It had received quite a bit of upgrades and now runs Windows XP and even has 384MB RAM. It's also incredibly fast for a PC that old for some reason, that is, it's very responsive, although it does take time to process things. We use it as the machine for floppy reading and writing and maintenance for embroidery machines (which are also quite old).
The second oldest PC is an old laptop, HP Compaq NX9030. It's like burnt out or something now. Quite unresponsive compared to the PC there, although it was capable of running Unreal Tournament 2004 on medium settings back in the day. I really don't have any idea about what happened, even reinstalling OSs doesn't work. But my brother still uses it, and he claims that he's fine with it. (Blatant lies, but he's too thrifty to admit it
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The others are still in very active use. The next PC we had is now used in my mother's work place, the one after that is in my brother's house and the next two are here at my home.
Another interesting thing with old computers came up today in my school. They used a bunch of really old, slow PCs in computer classes earlier, but then got a sponsor which provided both classrooms with new shiny PCs (dualcore and such, really top-notch pizzaboxes for our uses). The old PCs are now being integrated into the network and being set up in classrooms other than IT. (There is also a store-room filled with electronics from the old PCs somewhere. The view is spectacular to say the least.) And there are I believe 6 PCs that are now in the reading-room, full with an internet connection for everyone to use.
However, only 5 of those are in use. The last one caught my eye, though. First of all, it had a mouse mat, but no mouse to begin with. Then, it had no way to turn on the monitor from what I could see. However, the PC's lights were on and it seemed to be working. I managed to find the monitor's on button (it was situated on the side of it for some odd and ancient reason). It revealed Windows XP and the fact that the PC was incredibly slow. And I mean really. Like you wouldn't believe. When idle and you try to do anything, it will probably take around a minute for it to do it. Not just running programs, but also things like menu display. It even renders the default WinXP wallpaper a few lines at a time. I really don't have much of an idea about why it's like that (possibly a virus at work, it really can't be that slow normally), but that allowed me to have some fun with it.
First of all, I killed off explorer (remember, no mouse!), then called up the command prompt. Then went into fullscreen mode. From there I explored a bit, then launched firefox (took a long time), then downloaded the Lynx browser (zip archive). Unzipping it was quite difficult, however: .zip extension was assigned to WinZip, a trial version that was long expired. The menu also showed that 7-zip was installed...but in Russian. That means I have no idea what to press to extract it. Luckily, under Open With there was a choice of Compressed Folders. I managed to install Lynx, then closed Firefox, went back to the command prompt and launched it. And there, a fully working PC again! Doesn't lag a bit! No fancy graphics, but it at least worked and allowed you to browse the internet without lagging. And do anything else for that matter, as long as you know how to handle the command line.