Since I don't know you, I have to start with the simple questions...
Have you connected both the PSU's ATX and ATX12V cables to the motherboard?
After connecting the PSU to the motherboard and plugging the PSU into A/C power, do you see the (typically green) Standby LED on the motherboard lighting up?
Have you properly connected the front panel power button (etc.) to the header on the motherboard?
When you press the power button, are you seeing the other LEDs on the board lighting up? The fans starting to turn?
Hope this helps,
Yes indeed. I have connected both the 24 pin and the 4+4 pin connectors to the board. The front panel button is connected. I am using it to try to boot up. I am getting power to all fans including the CPU fan and the DVD drive is powered up, and so is the HDD. There are no LEDs on this board but only the locking clips on a couple of PCIe slots appear to illuminate with a cyclic increasing decreasing glow. I have no boards installed in any of the expansion slots.
This is a new build using new power supply (Seasonic S12II-520 Bronze), new MB (ASUS Prime H270-Pro), new CPU (Intel Core I3 6100 BX8066213600 3.7ghz, new memory (Crucial CT2K8G4DFD824A 16gb kit 2x8gb DDR4-2400 UDIMM, and new Western Digital Blue WD5000AAKX 500gb SATA HDD. All components deemed to be compatible according to manufacturers website info. I get no signal to the monitor from HDMI or DVI outputs. Monitor and cables have been tested on another PC and they are good. A second monitor has also been tried. All drives and devices have been disconnected for testing in case of conflicts. I have tried both sticks of RAM in all the slots one by one and in pairs. Also tried with nothing plugged into the expansion slots and various combinations of other hard drives. Without anything on the monitor I can't get into look at BIOS settings, etc.
Since you've emphasized it in umpteen places, let me say this: 'new' means absolutely nothing. With the horribly shoddy testing of components coming out of China, the only component in your list that I would actually trust out of the box is the processor. It's the only component in your list that we can actually say has been fully tested before shipment (each and every processor must be fully tested in order to lock down speed bin, thermal settings, etc.). Unless you can show that another processor works fine in this motherboard and with these other components, you cannot say that the processor is responsible. Feel free to contact Intel directly (returns are not handled through this site) if you would like to blame it on the processor (Intel will replace it, since they have this no questions asked policy), but I do not believe that it is responsible (well, not unless you handled it improperly (you were working on a properly grounded surface, wearing a grounding wrist strap, etc., right?).
Yes, I do use an earthing strap. I used to work in electronics and am aware of the risk of static discharge. I tend to stress "new" because I keep getting asked if a component was working "before". The only part of this build that was working before is the monitor. And the monitor still does work. I'm using it now on another PC.