I just tried to downgrade from 2.71 to 1.5. It had a TA-801 motherboard. I used the easy installer and ran it all properly. This is my first brick, so i feel kinda bad, but it's not my PSP . At the end....it says to "press x to restart" and I did and restarted. I had my psp plugged in with the charger the whole time. Then when I restarted... It was just a black screen. No backlit and No memorystick ledlight flashing. Just the Power led light on. It does not shut off either... just stays on forever. I see nothing...like a psp turned off with the power led lit up. Is there a way to unbrick this PSP. I will try ANYTHING. . After this... I recommend that after you press x to restart.... restart within 20 seconds or less. Probably less chance of bricking.