As it happens, I do run Windows 8 on older PCs. But, testing operating systems is part of what I do for a living. Unless that's also part of your job description running Windows 8 on an older PC is just a waste of time.
Oh sure, Windows 8 does boot faster and it has a few new features, but generally speaking Windows 8 with its “not Metro” interface is junk. I've been working with Windows 8 in one version or another for months now and there is simply nothing about it that would make me recommend it over Windows 7 or XP for that matter.
Metro, no matter what Microsoft wants to call it, remains a usability nightmare on a conventional PC. It may or may not be as awful on a touch tablet—I haven't tried that so I don't know—but I do know it's annoying as heck on my non-touch enabled PCs. The desktop, no matter what Microsoft may want, still works best with a Windows, Icons, Menu, Pointer (WIMP) interface, not Metro's big, klutzy tiles.
Want to have malicious fun? Stick some poor sod in front of a Windows 8 system and then watch them try to back out of an application. Watch them look around for the now missing in action Start button and hunt for the windows controls on the desktop screen eating application. If they're lucky they'll eventually stumble over the invisible lower-left corner escape hatch to the main interface. Oh yeah, this is so much better than Windows 7's Aero interface.
Here's the real point. Most people upgrade their operating system only when they get something better from it and there's nothing significantly better about Windows 8. Indeed, since Windows 8 requires you to relearn a lot of what you already know about Windows, it's actually a giant step back in productivity.
If you want something better than Windows, go with desktop Linux, a cloud-based Linux desktop like Google's Chrome OS, or a Mac. Heck, try an iPad. Just don't waste your time with Windows 8.
You say you really want to try something better than Windows on your PC? OK, if you're not much of a computer wizard, download a copy of Ubuntu 12.04. Don't be scared. My 80 year-old mother-in-law can run Ubuntu Linux so you can too. If you fancy yourself a knowledgeable computer user and you want something that looks and feels a fair amount like Windows, then try Linux Mint with the Cinnamon interface. Think you can along with just a Web browser for 99% of what you do? Then give Chrome OS a try.
With all these Linux choices, you can try them out from a CD or USB stick without changing a thing on your PC. You can also do this with Windows 8, with Windows to Go, but that requires a USB 3.0 drive with at least 32GBS of storage. Pretty much any USB drive will let you do it with Linux.
If you really must try Windows 8, and you don't have a Microsoft TechNet or Microsoft Developer Network (MSDN) subscription, you can download a 90-day Windows 8 evaluation copy. For some reason, Microsoft has made it impossible to upgrade from this version to a real version. So, even if it turns out you like Windows 8, you won't be able to keep using it. That's not much of a problem since I doubt most of you will still be using Windows 8 after 90-days anyway.
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