I only have a 460 watt and I dont want to upgrade power supply which are water cooling ready?? Is the 460 a good choice and water cooling ready?
Water cooling ready label on a 460W power supply simply means you can power a water cooling loop with it. It doesn't mean you can power a high-end water-cooled system with it. Purely a marketing ploy.
What is the make and model of your power supply?
That will help determine any suggestion regarding a video card.