In order to make use of the following Guitar Hero 3 – Legends of Rock game cheats for Xbox 360, you will need to strum chords or notes. If you wish to deactivate the cheats, simple re-enter the cheat codes.

Guitar Hero 3 – Legends of Rock Game Cheats:
Unlock All Songs in Quick Play Mode
Click on options and proceed to the Cheats menu bar. Click on the following buttons. Be sure to follow the pattern provided below:
Yellow + Orange, Red + Blue, Red + Orange, Green + Blue, Red + Yellow, Yellow + Orange, Red + Yellow, Red + Blue, [Green + Yellow]x2, [Yellow + Blue]x2, [Yellow + Orange]x2, Yellow + Blue, Yellow, Red, Red + Yellow, Red, Yellow, Orange

Unlock Performance Mode
Go to the options menu and hit on the Cheats menu bar. Press the following:
Red + Yellow, Red + Blue, Red + Orange, Red + Blue, Red + Yellow, Green + Blue, Red + Yellow, Red + Blue

Enable the Hyperspeed Mode
Go to the options menu and hit on the Cheats menu bar. Press the following:
Orange, Blue, Orange, Yellow, Orange, Blue, Orange, Yellow

Flaming Heads
Go to the options menu and hit on the Cheats menu bar. Press the following:
Yellow, Orange, Yellow, Yellow, Orange, Yellow, Yellow, Orange