You might check the +5SB (standby) out of the PSU. If it's dead, the power controller circuit on the motherboard won't work. I expect though that since you say there's something burned around the ...

NZXT has launched two new motherboards for Intel 12th Gen processors - the N7 and N5 Z690. Both use DDR4 memory rather than pricier DDR5, and retail for $300 and $230 respectively.