new build but no boot
PCSPECS
Intel Pentium 7th Gen LGA1151 socket
DDR4 HyperXFury Rams
700W PSU



Try to reconnect the cable or change the cable you used to connect the power button to motherboard.


resit everything, but now The fan spins for 1 second then the pc shuts off.


Did you unplug and plug in back the cable from mobo too?



Yeah, the rams are properly seated.





