Take one of your P3'* out of the box and look at the sticker on the magnet for the model number.
If the model number is;
P3D412 = DVC 4 ohms per coil
P3D212 = DVC 2 ohms per coil
Here are the links for the 2 different P3'*
Click on the woofer wiring tabs on the bottom of these links, to see wiring config.
4 ohm DVC
2 ohm DVC
Is this the Amp your looking at buying ?
Click on the Specification tab at the bottom of the linked page.
This amp can handle 1, 2 & 4 Ohm loads
The load on the amplifer is determined by how you wire your subs.
Think of it this way the amplifer has eye'* and can only see what ever resistance you show it by way of wiring your subs.
Less resistance = more power (unless you drop the load too low then you put the amp into protection ex. 0.5 ohm load)
750 watts x 1 at 4 ohm
2000 watts x 1 at 1 ohm