1st time builder here and I have my PSU (thor 850) and Mobo in case and all wired up. But am waiting on the CPU and RAM. I powered it up to see if my Mobo would light up as it has Bios feedback and it did but no lights or anything from my PSU. I am hoping some here could tell me if the PSU needs a CPU to activate. Otherwise it may be a while before I install a CPU and I would want to know if im returning my PSU.
With the AC connected the motherboard will receive power just fine without a CPU installed. However, the only functionality that will work (besides lighting) is USB Flashback. You can try using this functionality with the power supply installed.