My motherboard gigabyte b365 has wake on lan which normally works. However if power is removed, meaning I shutdown the pc, unplug it, wait for about 10min, then plug it back in, it does not wake up. For it to work again I have to turn on the PC manually for the first time and it works after that. But in another case - I shutdown the PC, unplug it, plug it back immediately without waiting for 10min, this time it will wake the PC. I want to know where the problem is and why it does not work in the 1st case but works in the 2nd case and any solution to make it work in the first case also. Just to mention I have a router with OpenWRT firmware if it helps.