Can you give us specific parts you used? Like what power supply, motherboard, cpu, etc..
Do you know the brand and model of psu?
Got the standoffs under the board in the right places? Got the 4/8 pin CPU power connector plugged in?.
Do you know the brand and model of psu?
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I am guessing you havent put the CPU cooler on properly. Does it give you anything on the screen, or any beeps?
try to plug in an extra fan to the motherboard. look at where the cpu fan is pluged in. there should be at least 1 or more inputs that look similar on the motherboard, and try putting a fan on those headers. some pre-manufacture boards are picky when it comes to having fans pluged in (mainly dells). let us know if this helps.
any way to just turn it off cause i know its working correctly, i was told to just turn off the warning