Unfortunately it looks like I spoke too fast...
Yesterday after installing the RAM I rebooted a few time, then play for a few hours without issue, that's true, however after playing again, then rebooting several more times today, I noted that apparently my PC is having random boot issue since I install the G.SKILL RAM and enable D.O.C.P. (never had this issue before with Corsair RAM with no D.O.C.P.).
So the issue is every few cold start or reboot, the PC is powering on, then powering off after a second, then power on again and then boot normally (no error shown this time). But it still looks like computer having issue during POST. But then, after a few more reboot, for no reason, the PC isn't rebooting at all, then it shows the error message "This computer POSTed in safe mode, if you changed something in the BIOS settings and blablabla", then it returns to BIOS. Then the only way to boot up my computer is to disable D.O.C.P. and reboot.
My BIOS is already up to date (as indicated earlier) and this specific RAM part number is certified by ASUS in the official Qualified Vendor List. Any suggestions??? 😕