Yesterday, I tested Debian Live 7.6 with non-free drivers using a USB stick. I used that because the completely-free version was not recognizing my wifi and video drivers out-of-the-box. Everything went fine, got everything working - audio, video, wifi, card reader, etc... so I decided to install. I restarted my laptop and began the installation process, which was successful.
When starting the machine after the installation process had finished, the only thing I got was a black screen. The ttys where available and working, though. I was able to manage the issue upgrading to testing - that was my goal after installing the OS in the first place, so I didn't even take the time to properly troubleshoot the issue. So, I just changed the sources.list repositories to point to testing and issued an aptitude safe-upgrade. After that, everything was working.
Why the machine worked fine while using the Live USB stick, but then it failed to work when the OS was finally installed in my machine?
Does the Live distro use some other way to recognize the hardware, so it's able to handle more scenarios than usual? Does it do some kind of fail-safe run in order to ensure the system can load and be usable?
I'm not trying to debug the problem here - I'm just trying to understand why the Live system have worked, but then when the OS was installed it's not. What have changed between the 2 runs?
