Does having a registry full of old stuff slow down Windows? [closed]

Question

I know this isn't strictly speaking a programming question but something I always hear from pseudo-techies is that having a lot of entries in your registry slows down your Windows-based PC. I think this notion comes from people who are trying to troubleshoot their PC and why it's running so slow and they open up the registry at some point and see leftover entries from programs they uninstalled ages ago.

But is there any truth to this idea? I would not think so since the registry is essentially just a database and drilling down to an entry wouldn't take significantly longer on a larger registry. But does it?

EDIT: To be clear, I'm not looking for advice on how to make a PC run faster, or asking why my PC in particular is slow (it's not), I'm just curious if people who say "bigger registry means slower PC" are accurate or not.

Answer 1

I think its a symptom, not a cause, as fever is a symptom of an infection.

When you install windows updates, at least in xp and up, a folder called SXS is maintained for rolling them back. These rollback points are also stored in reg keys.

The size of the sxs(side by side) folder grows exponentially and definitely has been linked to why, when some people simple reinstall with sp3 instead of installing sp1 and rolling up to sp3 they get better performance, even with the same programs installed.