Short answer: No.
In the startup time department, supposedly, Windows 8 has a much faster startup time than Windows 7. It also starts up from sleep mode in a few seconds, rather than 10+ seconds in previous versions of Windows. In that respect, sure, your PC will be faster under Win 8. However, startup time is not a good measure of PC speed, not really.
Consider also the learning curve that you, the average PC user, will have to travel to get used to the radical new Metro user interface in Windows 8. Even Internet Explorer is doing away with traditional menus in favor of a Ribbon interface similar to recent versions of Microsoft Office. In that respect, your PC experience will actually be slower, at least at first.
Also consider the bugs that accompany every new major operating system’s release, especially one like Windows 8, with an instant installed user base of millions of people. Some of whom have really bizarre system configurations and are going to crash, a lot. A lot of experts advise you to wait until the first Service Pack (a huge Windows Update filled with bugfixes and security updates) before using a new OS. That may be a good idea in this case, too.
Will Windows 8 make your PC experience faster? Not really. Different, yes. More intuitive, yes. But not faster. Will it make your PC more reliable? Not really. It’s likely to crash more at first than your patched-to-the-gills Windows 7 does. And if your hard drive has errors or your memory is faulty, then no new operating system will help those problems.
The reason people are going to go out and get Windows 8 is not for faster or more stable PCs … it’s to take advantage of an operating system built in a modern-day context, designed for online users, touchscreen users, and Web-centric users. Going faster isn’t really the point.
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