I have AMD radeon 7470M 1gb garphics card, i installed ubuntu in the nomodeset, after my first boot, i jst opened it from boot screen by pressing 'e' and replaced “quiet splash” with "nomodeset", it worked fine i can login but after that i installed AMD catalyst drivers for my graphics card, they are not working and even i opened the rc.local file as the root user 'sudo nano /etc/rc.local' copied and pasted the following lines just before the line exit 0 :
chown -R $USER:$USER /sys/kernel/debug
echo OFF > /sys/kernel/debug/vgaswitcheroo/switch
it doesn't work for me, even time which i boot to OS i need to replace "quite splash" with "nomodeset" by pressing 'e' in the boot screen, then only i can login to Ubuntu.
How can i fix this its very difficult for me every time i should replace that thing.