crossfire question

[karl01]

Ive got a old motherboard
An asus P5Q PRO (p45) socket 775
Its got 2 PCI Express lanes one i no is definialty 16 lanes but not sure about the other one does the colour of the PCI Express socket tell you how many lanes it is? I want to get 2x5770 in cf can anyone tell me if i can crossfire with this motherboard?.

 

[karl01]

So if they both run at 8x speed is this going to effect the overall performance or i am still going to see a good performance?

 

[karl01]

2-5% i can live with that going to order now cheers pal.