Flashing GTX560 Palit EFI

hello to all guru,
I'm new, and I speak very little English ..

I would like to ask for help,

I have a card that does not use, a gtx560palit.
http://www.palit.biz/palit/vgapro.php?id=1804


I would like to put it in my MacPro 5.1, instead of the old GT8800.
I have test it, and work fine, but not see a boot logo.

Can you help me to flash it to boot?
I would like to activate at least 2 digital ports,

I have to connect a 30" and a 17"

many thanks