a. Turn off PlayStation 3.
b. Turn it on and keep Holding The power button down; The system will turn on and turn off once again. BUT MY PS3 DON'T TURN OFF
c. Once the System has been shutdown, Turn it on again and keep Holding The power button down (you will hear 1 beep first, keep holding) until you hear 2 consecutive beeps
d. When you hear the 2 beeps take finger off power button.
e. You will be prompted to plug in your controller via usb and then hit the PS button
f. The Recovery menu will pop up.
g. Last Option #6 is what you must use "System Update"
I've just successful install Rebug 3.55.3 REX EDITIONS, but i can't still boot to Recovery Mode to do something useful. Rebug toolbox can't do too.