Frozen Fractal
Distinguished
turkey3_scratch :
I know there are water coolers for CPUs, but do they sell things like this (water coolers for the entire computer) already pre-assembled? I'm not sure if I'd want to go through that tedious process, and I'd be willing to spend a bit more and buy a pre-made system water cooler. But do they even exist?
Yes, you can find pre-assembled PC with WC loop these days, although they cost much higher (well that's just a common downside of WC loop anyway, nothing to blame these retailers). XOTIC PC, CyberPowerPC and of UK, Overclockers UK are some among the many places where you can get one.
turkey3_scratch :
Also, what's the difference in the radiator and pump?
Pump makes a fluid flow (in this case, the coolant) and the radiator cools the coolant with fans blowing external air through the radiator. Essentially a pump emits few wattage of heat, as the OP says, somewhat of 20W, and that gets added with the total heat to be dissipated by the radiator.