Do you still have a PC running an older version of Windows?

My main rig is a i7 4790k, with 32gb ram and NVIDIA GTX 970. It's getting old now, but still does the job. I also have a Compaq desktop with a Pentium 3 inside, but the previous owner was a dolt and it got damaged in transit - will repair it when I can. I also have a HP Pro 3010 MT with 4gb ram, XP/Win2K dual boot on that.

I have multiple other systems as well, most of them needing new OS installs. Nearly all of them are early 2010s Optiplexs, but I also have a HP dx5150 which I hope to install Win98; it has 512 ram and AMD Sempron 3200, so it seems like it seems doable, on paper at least.

Update to this: finally got around to trying to do this. Install went well, at first: sound doesn't work, but I got the GPU drivers to work, and I was able to get W98 to display at up to 1080x1440, which is odd to see. Sadly, everything went downhill after as I can't seem to boot into the machine without first starting up safe mode and then rebooting from there and for some reason the system hangs randonly on it's own.

Turns out I need chipset drivers and they didn't make them for Windows 98/ME for the machine I have, so it' appeas I'm SOL.

Only ray of light is someone is selling refubished machines on Ebay with near enough the same setup as me and managed to work it out by installing unofficial updates and an older version of the SB400 drivers. So I may be able to salvage this - if not I'll just slap an old build of Linux on it.

EDIT: I gave up and installed Win2k on it.
EDIT2: Screengrab: i.imgur.com/AjJoCZS.png

Vista is a bastardized rework of 7 what microsoft did with the mojave experiment was to rollback to 7 and drop the vista project , vista was too advanced for poor hardware and pretty buggy (still is) in 7 they removed the startmenu and got a hard to use 2 panel thing instead there was no switching back until classicshell. Since then they have been keeping slaughtering the UI
Technically we need a perfect 3rd part ui that works on all windowses and uses all the classic apis but new ones too that way if they remove something we can always add back the reg entry for it in a way the ui would understand.

That is what they want you to think they actually went back before they implemented the Start menu fully thats why you still need classicshell or you be stuck with that terrible improved startmenu , i got friends working at ms telling me of this rollback basically vista is a different beast that was going longhorn while windows 7 is the mojave experiment a rolledback prevista with features removed.
Sct is a software full of errors for now its best to use classic3 theme in startisback unless it evolves to be more compatible and not require .net or sctt and stop giving errors even though i followed all the instructions . Then again im on a very lean modded version of windows and the dev might use a buncha crapware that i deleted such as windows offender or whatever its called.

Even the C++ rewrite is going to require libraries (VC++ Redist). The only reason why SCTT says it requires .NET is because it uses a newer version of .NET which is lighter and faster than .NET 4. The only problem is that Windows doesn't come bundled with it, like it comes bundled with .NET 4.8. Because time moves forward and not backward, a future Windows 10 version will probably already include this which removes the need to install it altogether.

On my own, that's probably going to take another year. SCT Taskbar C# costed me 8 months to get it to a state where it was usable. And that was with me being pretty much fluent in C#. I'm far from as good in C++ as in C#. Honestly, I don't even believe I can get it as optimized as the C# version. The C++ version is some magic dream version that probably won't even be finished. It's just a project I've began working on because I thought it would be a good way to expand my programming skills.

Windows Defender  in xp days windows security essentials full of backdoors for microsoft but once its gone pc works better

Update to this: I ordered a new refurbished replacement motherboard a few weeks back and finally got the new one today. Hopefully all it takes is swapping out the old with the new and I'll have a working Win98 PC by the weekend. 

That's nice. Also, that means having/enjoying some experience of the 1998s OS (Win98). Although, Windows 95 can be used for real as an app: github.com/felixrieseberg/windows95 (yeah, ikr that it's a horribly old OS, but i just saw that thing being an app last year.)

And as to the OP of this topic: Yes, I once had a laptop having Windows XP (but the screen was slightly covered), and that one used to have the battery depleting, giving me out some battery low and critical alerts & sounds, shutting down my computer, and also a laptop once with Windows 7 which was Home Premium (and I had to use Anytime Upgrade to make it Ultimate version), and that one was slow as heck, and lagged a lot. The battery also was at 0% sometimes (even when plugged in). Then, by luckiness, I switched over to a laptop (with windows 10) before the end of Windows 7 support (Jan 14, 2020)