Review on Coolmax I-400 240-Pin 400 Power 💨 Supply featuring Low Noise Cooling Fan (80mm) by Luckie Coonrod

I bought 2 of these Coolmax 400W power supplies. I hooked one up to an Optiplex 9020 and figured I could put a decent graphics card in this Dell. The problem is that I raised the power button, I got power for about 2-3 seconds, then the fans stopped and won't boot. Press the power button several times, but there is no power. I turned the power off, then back on and got power and the computer booted up. Turn off the computer and try restarting the power button a few times before I got power which lasted 2-3 seconds. Switched the power supply off/on, pressed the power button, switched it on and booted the computer. I tried it a second time and got the same results. I tried the EVGA 500w PSU I had for another build and it works just as well as the stock Dell 290 PSU.. Now I have 2 paperweights that I don't need or need. I've used Coolmax power supplies before with no problems. I will no longer use Coolmax.