Screen goes black after I/O board replacement

I recently changed my I/O board with a new one and afterwards my screen would go black for a few seconds and then come back on. I switched it back to my old I/O board and its working fine now. Is there something that I missed when I put in the new board? By the way, I was changing out the old board because of some issues I was having with the Mag Safe port not staying connected. It seems to working okay now as well.