I've recently upgraded to 12.04 LTS and I have an ATI Radeon HD5670. I've heard that the open source 'Radeon' driver is used by default. However, it wasn't showing anything for me. What I did was I added the 'nomodeset' option to boot up and install fglrx. But it didn't work well for me as it introduced a lot of problems (freezes/glitches). So I removed/purged fglrx and am planning to use the open source drivers instead.

So my question is this: Why is my default Radeon driver not working? Is anyone having a similar issue? I've also tried using the ubuntu-x-swat driver by running the ff commands:

sudo add-apt-repository ppa:ubuntu-x-swat/x-updates

sudo apt-get update

But the result was the same as the Radeon driver. Nothing shows up on system boot. Any ideas? Thanks in advance!

Update
Running lspci -nn | grep VGA gives me the following:

02:00.0 VGA compatible controller [0300]: Advanced Micro Devices [AMD] nee ATI Redwood [Radeon HD 5670] [1002:68d8]