In reality, registry entries aren’t a drag on your computer’s performance. The registry is a massive database containing hundreds of thousands of entries and individual registry entries are fairly tiny. Even removing a few thousand entries won’t make an appreciable dent in the size of your registry.Now, if our computers only had a tiny amount of memory or an extremely slow hard disk, there could be some value to shrinking the registry a bit. But this will be completely unnoticeable on computers in use today. We don’t live in the days of Windows 95 anymore. The Windows registry has also become more robust as Windows itself evolved from Windows 95 to Windows 7 and 8.
Windows just isn’t getting confused and slowing down because you have a folder (known as a “key” in registry parlance) dedicated to an uninstalled program in your registry. It also isn’t getting confused because certain entries point to an outdated program.
No legitimate benchmarks showing a performance increase as a result of a registry cleaner have ever been released. If a registry cleaner offered boosted performance, we would have some benchmarks by now. It’s anecdotal evidence, but the majority of our readers didn’t find that registry cleaners helped improve their performance on modern computers, either.