Hey. I have a question. In my current build I have R9 280x and 4670k powered by XFX Core 550W PSU. I need to replace my card because I'm giving it to my sister and Im buying Sapphire R9 390 Nitro. I was wondering if the XFX PSU is good enough to run the system, or do I have to replace PSU as well? I've heard quality 550W PSU would be enough, but I'd rather ask you too.