I had a 667 DVI working fine...cept it wouldn't take an AC adapter. I bought an 800 Mhz DVI logic board....swapped it in.... it worked, but now the LCD doesn't want to turn on... i put back the 667 logic board and still the LCD doesn't want to turn on. I put a light thru the apple and there is no video coming up so it's not the inverter board. Any suggestions guys?