I've installed Ubuntu-12.04-LTS-desktop-i386 on AMD desktop recently. No problem on recovery mode but it shows grains like screen on normal boot. I can't even read anything.
As mentioned in the chat, find out what you video card is (
sudo lshw -c video) and install the correct drivers for it when you have booted into rescue-mode/resume. You might have to reinstall it after rebooting into the normal system (not sure, but I read that once somewhere).
The reason seems to be that a normal boot uses the xorg-related video drivers, while the Recovery-mode/resume option boots with llvmpipe as low-graphics fallback driver. And the normal xorg-driver seems not to like your graphics card...