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I installed Ubuntu 12.4 on 8GB USB Flash drive. It went OK. But when I reboot it goes to Blank screen. IF I press Shift the (GRUB loading) msg on screen. Fan starts so I assume ATI HD6770M graphics card gets control. I've to press and hold power key to close.

BIOS is set to dynamic but changing to fixed doesn't help. Flash drive boots ok on my 32bit desktop. How can I turn ATI card off using Live-USB? ATI card has no problem with WIN7, HP will not help. I've been trying to reinstall ATI drivers, Changing boot options in Grub but nothing helped.

Driver HP dv7-6b00et

At this point, I've tried this:
I selected to stop ATI card. Used a live-USB, Mounted ubuntu.
Installed flashdrive, chrooted, and became root. Edited /etc/rc.local to add:
modprobe radeon
echo OFF > /sys/kernel/debug/vgaswitcheroo/switch

The /etc/modprobe.d/blacklist-local.conf file was empty so /etc/rc.local:
add blacklist fglrx
REBOOT ===> blank screen

I make /etc/rc.local EXECUTABLE

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Current: Bios set to FIXED and GPU of INTEL selected.RADEON gpu is not ACTIVE. – Orhan Toprak Jun 6 '14 at 20:04

The HP DV7 notebooks are not fully compatible with Linux, especially the AMD Radeon graphics.

There are multiple threads about this issue on Ubuntu's official forums, but I am uncertain what the best options are. Here are some threads/pages you should read before considering your options.

Description of Hybrid Graphics and instructions on how to disable the Radeon graphics if using the open-source drivers:

Instructions for updating Catalyst drivers:

Reference to a thread about disabling the Radeon graphics, poster considers it the best option:

Instructions for turning off AMD Radeon graphics: *

Similar thread here on AskUbuntu: How to switch between GPU's on HP Pavilion DV7 Laptop?

Long thread about... well, I have no idea, but it's long: *

* Be aware that these threads were started prior to 12.04's official release and may contain outdated information

I don't have an exact answer for you, as I have not dealt with the incompatibility issues myself (though I was definitely looking into buying an HP DV7), but the links explain your options and have step-by-step instructions.

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I edit /etc/rc.local add – Orhan Toprak May 16 '12 at 9:10
modprobe radeon echo OFF > /sys/kernel/debug/vgaswitcheroo/switch – Orhan Toprak May 16 '12 at 9:11
Problem is Grub bootloader. İnstalled PCLINUXOS on usb hdd and stick – Orhan Toprak Sep 20 '14 at 18:47
Installed PCLINUSOS on USBHDD and USB stick both Boots OK. Bootloader is vmlinux – Orhan Toprak Sep 20 '14 at 18:58

Thanks Michael I selected to stop ATI card. USED live-USB, Mounted ubuntu installed flashdrive chrooted and became root. Edited two files /etc/rc.local add: modprobe radeon echo OFF > /sys/kernel/debug/vgaswitcheroo/switch and /etc/modprobe.d/blacklist-local.conf file was empty so I copied first 2 lines of /etc/rc.local add blacklist fglrx add exit 0 REBOOT ===> blank screen Should I make these two files EXECUTABLE if yes how?

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