I want to water cool my gpu, seeing a lot of these radiator mounted pumps on many websites, they are mounted to radiators usually that are lying flat attached to the top of the case, I was under the impression that you are supposed to keep the pump as low as possible, are these rad mounted pumps different?

I don't have the space for a pump res combo so this would be a nice alternative, but I can only mount it at the top of the case.