displayport v 1.1a?

Hi all.

I have a mid-2009 core2duo 15" Macbook Pro unibody with mini displayport.

I want to buy a monitor and connect it via a displayport cable, but the apparently the monitor I want has a displayport v 1.2.

I'm pretty sure the mid-2009 MBPs use Displayport v1.1a (going by the timeline of the displayport standard)

I appreciate that miniDP has been officially recognised as part of the DP standard, but this occured late 2009, after this range of macbooks had been released.

Does anyone know whether it is displayport v 1.1a or 1.2 in my MBP? And either way, since I'm only planning to send video up this cable, does it matter? (my understanding is DP v 1.2 simply adds audio support, and was placed in the MBPs in mid-2010).

Struggling to find info on this.

Thanks