The other day I upgraded from Ubuntu 12.04 ("Precise Pangolin") to Ubuntu 12.10 ("Quantal Quetzal"), but when I logged-in afterwards, all I'd get is a blank desktop!

Seeing as I needed a new installation disk anyway, I figured I'd just do a "clean" install and start from scratch which in theory, should fix the problem...

But I am now experiencing the same problem!

I saw a YouTube video that explained the issue may be because propriety drivers are being used (I elected to use these after the first login) and it explains that there was some change to the drivers used in Ubuntu 12.10 ("Quantal Quetzal"):

However the process he describes does not work - I still have the same issue after entering the applicable commands in Terminal and rebooting!

Any help would be appreciated...

I'm using a Sony VAIO VPC-CB15FG, with dual graphics cards - an AMD Radeon HD 6630M and Intel HD Graphics 3000.

It is the 64-bit version of Ubuntu 12.10 ("Quantal Quetzal") I have installed.