Are both ports the same on the XC7 RGB Elite CPU Water Block?

All modern CPU water blocks will have a specific port that is used as inlet. The reason for this is that most blocks uses a jet-plate design which forces the inlet coolant down into the cooling fins from the middle, instead of just from one side to the other side.

Since the XC7 RGB Elite also utilize a jet plate design, the inlet and outlet are very specific, and shown in the above picture. When mounting the XC7 to your loop, you will want to use the bottom port as inlet, and the top port as outlet.

Whether you will see a performance difference depends on many different factors such as the power draw of your chip, the flow rate of the system etc.

As to the question of "can I use the inlet as outlet" and such, the answer is often that in special circumstances where your only option is to use the inlet as outlet or vice versa, you can do so, but should expect slightly lower performance on the block.