Hubris UPDATED

Wrote this letter to the computer guy last night. I haven't sent it yet.

HI Geoff;
I got my wonderful beautiful new computer home OK the other night, and I opened it up to look at it and one thing led to another and now I am afraid I have made a series of extremely ill-advised and quite possibly destructive mistakes.
You see, Geoff, I'm a kind of an artist. I'm creative. I am busy all the time making stuff. I needed a sail for my traditional wooden boat, a Grand Banks Dory just like they used to use in the codfishing industry back east so ai got dsome books and I am making a traditional old-time canvas sail with all the lashings and reefing-lines and everything just like they were in the old days, and you know I make all my own ropes. A sail needs a mast, so I got a piece of salvaged 3x4 douglas fir 12 feet long and I made it into a mast using hand tools in the old-time sparmakers fashion and it, and the sail and the ropes are beautiful and highly functional. And I needed a new flannel nightie so I made a beautiful warm pink flannel nightie with lace and ribbon trim and it is a nice thing. I'm teaching myself how to make a really good county-fair-worthy apple pie. I needed a case for my netbook, so I took apart an old leather jacket and made a padded netbook sachet. A couple of years ago I made a Lynx-fur parka with walrus tooth toggle buttons, and I made a pair of matching pigskin gloves lined with Lynx fur.
My point is I make nice  stuff, complicated stuff, and I try to do it the right way.  I study up on how the big boys do it and I put in the time and the effort and learn technique. I do my homework.
Apparently not enough homework in this instance.
So there are some things I had been studying and thinking about to do with cabling and the arrangement of the drives and the harness and just the sheer hands-on. I wanted not only ownership, but authorship.
I  wanted more of a hand in the doing of it. As you may recall I said something about wanting to do the final assembly. I should have left well enough alone, but  I went too far. way too far.
I'm going to tell you exactly what I did even though I know now, and I sort of knew at the time, that I shouldn't. I feel terrible about how far in over my head I am.
I took the harness off the motherboard, and I took out the GPU. I wanted those red thumbscrews in there. I wanted to run the harness a different way. I am sorry but that is what I was thinking. I put the thumbscrews in,  and then I put the GPU back in and then I hooked up the cables, correctly, I thought, but routed the way I wanted them, and I rubber-wrapped the trunk of the harness and I made branch lines like they do and it looked beautiful. I found another black SATA cable so they are all the black ones now, 28 gauge for the SATA3 drives and 30 for the DVD.

If this were an actual rubber hose I would have black and blue marks all over my body.

I changed the run for the CPU fan and plugged it back into its proper header, as well as the case fan. I mounted another case fan in the top of the case. I had to mod it a bit to fit over the RAM but it clears them easily and I did not take the RAM out. I put that clip back on the back of the case over the expansion card slots that you said I didn't need, just because I, in my ignorance, thought it looked better that way.
And of course did something, or several somethings with predictable results.
Now I am back to no-power-up, no-POST.
I am so disappointed with myself but I cannot say I am surprised.
See, Geoff, when you plug in a wire, you know what it is and what exactly it is doing and why it is where it is and how it is. When I do it all I know is where I think it is supposed to go according to what looks like the picture on the diagram. I "know" what the drive is and does, but only by name and from what I have read. You know what it is and does by your life, education and systematic experience. And I don't mean to disrespect that, but I think I kind of did.
I have no idea where I went off the road here, and I am starting to think my worst enemy is my sense of adventure to do unknown things. I really really wanted to do this build and I did not know how little I knew about it. All these kids do this all the time and they make it look easy and fun. Well, it is fun, but not that easy, it is delicate and complicated and things have great meaning even if they look little and unimportant. There's more to this stuff than meets the eye, and I am sorry if it is insulting that somebody like me thinks they can do what you do,  without they have the education that you invested in and the hard-won experience that you have given your professional life to acquire.
Of course when it didn't even blink I took thos stupid thumbscrews out, and I took the rubber wrapping off of there.
And I would walk across hot nails and bring it and more money if you would try and fix this thing.

UPDATE: there's two little 4-pin headers way down at the bottom of the board that says CHA FAN2. There was a 4-pin mini-plug from the power supply that I thought routed the power through the board up to the actual chassis fan at the top. A separate fan circuit, or so I thought. NOT. Apparently you can plug in dozens of chassis fans to this board, which some guys do when they overclock and heat the system all to blazes. Not me. Luckily, if you make this mistake the board knows you fucked up and simply shuts down to give you an opportunity to reflect on your behavior and make deals with the gods concerning penalty and repentance.