I would not bother with a water cooler. Air coolers are fine. What are the rest of your parts and what cpu do you currently use?
GPU: amd r7 240
CPU: AMD FX(tm)-4300 Quad-Core Processor
Harddrive: idk but I got 1.5 Terra bites
Motherbboard idk what it is but it is ssome cheap brand one probably something you don't know