Hi there. I just built a new PC. Nothing happens when I turn on the power switch, except maybe a try on the part of the CPU Cooler fan and the PS Fan. I figure that the Power Supply is not strong enough. It only delivers 15 A and 237W at 12V Aside from my system load, which is basic at this point, I'd like to know if I can hook up another power supply without actually installing it in the chassis, just to test. Any concerns about grounding? Thanks in advance.