I built a small 3 card rig end of December, with a 1200W PSU so I could expand to more GPUs but the profitability has dropped noticeably in the past 30 to 45 days. Not sure if I want to invest more into the rig and more GPUs now. I had never built a computer before, so I learned a lot last year, reading articles and watching videos on how to do it. I wish that I had come across this forum for info earlier. I have not been able to get more than 29 to 30 Mh/s out of my PowerColor RX 580. I dont know if it is due to the brand of GPU, memory type, or just luck, but I couldnt find any other tricks to increase the hashrate.