I’ve used many different power supplies over the years to power my lighting projects however very few have lived up to my expectations especially under heavy loads. Many of the so called high current Chinese designs can have suspicious ratings to say the least with some being positively dangerous.
Your precious pixels need worry no more as an old ATX PC power supply with a relatively simple mod can offer a clean reliable high current power source, that will provide many years of service.
I’m not going into the construction side of things as below are some great links that provide all the info you need. The first guide is my favourite that I originally used 13 years ago.
My original guide - http://web2.murraystate.edu/andy.batts/ps/POWERSUPPLY.HTM
Any questions on modding, please feel free to ask.