Question Newly built PC turns on but the display doesn't work

Sep 22, 2019
When I press the PC on, the CPU fan turns on for a few seconds. The DRAM LED flashes red then turns off, then VGA LED quickly turns orange for a few seconds, then the CPU fan turns off. This happens twice. Then the CPU fans turns on and stays on as if the computer is working perfectly. There is no display however.

I have plugged in the HDMI cord to both the ports on the graphics cards and the port that comes with the motherboard. No display shows up. The cord works on the computer that I'm using right now and works on other computers. It's likely not the cord.

I also reseated the 8 & 24 pin PSU cables several times with enough pressure. The "cable seating" isn't the issue.

The CPU & the CPU fan were previously used but were in good condition. I suspect the CPU to be the issue, but I'm not sure.
Intel Core i5-6402P 2.80ghz (LGA1151)
Intel e97379 -003 fan (yes, the cheap one)

The motherboard is brand new
ASUS ROG LGA1151 (300 Series) DDR4 DP HDMI M.2 Mini-ITX Motherboard (Strix B360-I Gaming)

I've been reinseating these RAMs in all possible combinations within both slots please do not tell me to "reseat" them. You will be wasting my time and yours. I already did that. I installed both patriot sticks, then one at a time, then proceeded to install the Vengeance stick by itself within both slots. Nothing changed.
2x Patriot Viper DDR4 4GB 2133MHz CL15 1.2v
1x Corsair Vengeance LPX DDR4 16 GB 3200MHz 1.35v Intel e97379-003 fan

The almost completely brand new PSU was never actually used, but has been attempted to be used in other failing systems.
Thermaltake Smart 700W 80+ White Certified PSU

I've been alternating between these two graphics cards:
AMD Radeon RX 480 4G
Nvidia Geforce GTX 760ti 2gb Graphics card

I've tried Several hdd, hsdd, and flash drives as boot and or storage I didn't feel the need to list them
I tried to reset CMOS in this motherboard by shorting it. The instruction manual says that there is a jumper, but it does not have a jumper. I just shorter the pins anyways. I don't know where the CMOS batter is on this motherboard. I can't find it. Telling it "its there somewhere," doesn't help.