My new Z170 ASUS motherboard came with a case front panel connector similar to yours.  Mine also included a "CPU Installation tool" that made getting the CPU installed correctly easy and avoid any CPU socket bent pins.
 
 

Rob[atSound-Rehab]
Thanks for sharing all this detailed info. Makes excellent reading but it does scare me like s***. Pretty sure I'll have somebody build the next DAW for me.

Really curios how your thunderbolt experience will be!

Happy to share! I've done a lot of these over the years but it still intimidates me at times (like putting in the CPU). :) If you want more details on anything don't hesitate to ask..

fireberd
My new Z170 ASUS motherboard came with a case front panel connector similar to yours.  Mine also included a "CPU Installation tool" that made getting the CPU installed correctly easy and avoid any CPU socket bent pins.

 
I've never seen a tool like that but it sounds handy.
 
I'm keeping my fingers crossed for when I fire up the power button in a bit... 

Here's the ASUS instructions on the CPU "installation tool" (as they call it).
https://rog.asus.com/arti...cpu-installation-tool/
 
I hope the GSkill memory works OK for you.  One of mine failed already (less than 4 months).  I've had GSkill before that failed and I shouldn't have bought GSkill this time.  Its under warranty and I'll see what I can do to get it replaced (I remember I had to "jump through hoops" to get the failed replaced.  In the mean time I've bought new Corsair DDR4 memory. 
The GSkill I have is F4-3400C16D-16GTZ  Trident Z

......and it won't post. The error code indicates I might have to flash the bios to a newer version to support the CPU or the RAM. Of course, you have to be able to boot to update the bios. :/
 
Fortunately, I have two fantastic PC techs that work for me, so I'll take it to them in the morning. Hopefully they have an older CPU and slower memory lying around so we can get this sucker to boot up. If not, I have to tear it all down and I think send in the motherboard manufacturer to have it flashed.

I feel your pain. 

Z170 boards were designed for the later i7's such as the 6700/6700K.  There must be another reason.
If its a board problem, sadly, it could be a bent pin in the cpu socket (usually not repairable or under warranty).

Yeah, I'll be pulling the cooler at some point but I'm 99.99% positive that the pins are fine; I take a lot of care putting in the CPU. 
 
I believe the 7700k came out in January so it's very new. I might just have a board with one or two BIOS updates back. 
 
Fingers crossed...

Sorry about that.  I just looked at the spec's for that board and it states
"For 7^th Generation Intel^® Core™ processors support need to update the latest BIOS"
 
I was thinking of the Z270 boards that are for support of 7th gen CPU's.
 
But how in H..l do you update the BIOS if your CPU is not compatible?

fireberd
But how in H..l do you update the BIOS if your CPU is not compatible?

 
That's the chicken and the egg! :/ It says there is a way to flash the BIOS with a utility even if you don't have a CPU or memory installed.
 
My guys will figure it out - I'll post the resolution and then move forward with the build. :)