ok so I got the PW-120 PSU from ebay and it's claimed to generate 120Watts of power. So if I want to use this in the home 120V plug, I'd need a 120-12V adapter. The question is how many amps do I need. I can find to a max of 1500 mAmps on radioshack. Is this enough or do I need something like 5 amps? Thanks.