Question about network-manager and build-essential packages:
I decided to replace my old computers this year and so I had to install Ubuntu on the new desktop and laptop. I don't reformat any Linux partition periodically because it's fairly easy to maintain through upgrades without performance issues. So I forget a lot of the setting up I have to do and have to refer to notes I took a while back, a lot of which ends up being obsolete.
However, there is one peculiar issue with Ubuntu that never changed (no matter what the hardware) and I never understood. Ubuntu's Network Manager, on clean installs, can sometimes load very slowly. I get the internet connection itself working perfectly, but Network Manager will take a good minute and a half after the desktop is fully loaded to establish the connection.
Solution? Install the build-essential package. Then Network Manager loads promptly and works perfectly.
I'm merely curious why that is and why it's still an issue even on 13.04. This problem started on 10.x versions if I'm not mistaken.
Re: Question about network-manager and build-essential packages:
I have never seen the problem you refer to. Fresh install, the wireless network connects very quickly. It might be specific to your hardware.