I just upgraded my notebook to a HP dv6t Quad Core Edition (September 2011) with Intel Core i7 2630QM and powered by ATI/AMD Radeon HD 6770M Switchable/Hybrid Graphics Card.
Running Ubuntu / Linux Mint 11.04 64-bit on it has a few problems like:
- cannot boot Live CD / Live USB installer
- crash / kernel panic during boot / stack trace regarding radeon module
- cannot control screen backlight
- screen is blank (completely dark black)
- CPU / VGA / graphics / notebook fans are always on
- power usage is high / sucking up battery / battery life is short
First of all please check your BIOS (press F10 during boot) to see if there's a switch for Switchable Graphics to Fixed/Dynamic. Or check if you have BIOS version F.1A or later.
If so then the switch feature should be there.
If not then I suggest upgrading to the latest BIOS from HP website. Please contact HP for further information as I cannot provide support on this.
Which mode should you pick? In my experience either Fixed or Dynamic works fine, what matters most is blacklisting radeon kernel module/driver.
To launch the Ubuntu 11.04 / Linux Mint 11 (Katya) Live CD / Live USB installer properly, at the GRUB2 boot choices screen press "e" or <Tab> (if you use unetbootin) to edit the GRUB2 boot command as follows:
- remove : splash quiet
- add (before "--") : radeon.modeset=0 rdblacklist=radeon xdriver=i915
If you already installed Ubuntu / Linux Mint, follow these steps to blacklist radeon kernel module driver:
- Boot using Recovery choice (when prompted by GRUB2), or use Live CD / Live USB installer
- As root, create file /etc/modprobe.d/blacklist-radeon.conf with the following contents:blacklist radeon
- Save the file and reboot.
However even though you are using Intel graphics, the AMD/ATI Radeon HD 6770M graphics card is still powered on, consuming precious battery life.
To power off ATI Radeon HD card, as root, edit the file /etc/rc.local and append (before "exit 0") :
echo OFF > /sys/kernel/debug/vgaswitcheroo/switch
Save the file and reboot. Now you should have better battery life.
To check the Intel / ATI switchable graphics power state you can use:
$ sudo cat /sys/kernel/debug/vgaswitcheroo/switch
The "1:DIS: :Off" means the discrete graphics (ATI Radeon HD) is powered off, so it's deactivated and not consuming any power.
Right now pretty much everything (except the ATI Radeon HD graphics card, which I'm not interested in activating right now) is working on my notebook/laptop.
Next what we can also fix screen / backlight display brightness setting not working.
Find tips to optimize your Ubuntu 11.04 in Ubuntu Unleashed 2011 Edition: Covering 10.10 and 11.04 (6th Edition) !