I don't understand why you so skeptical about running dual gpu's with an 860, I have an AX860 for my build *see my sig* and it runs flawlessly with no problems.
That's on top of my rig being modestly overclocked as well, you have to understand that nvidia cards are a completely different...
Also since you're going for a silent build I highly recommend, Asus's version of the 780.
Asus GTX 780.
I have two myself for my build, and they are dead silent and the fans on it are the amazing in terms of keeping them nice and cool.
Like I said, any numbers you see are pretty much place holders until they recieve the official word, because if you look around some sites are even listing it at around $535. So just wait a day, won't due you any harm and you can confirm it yourself that way too. Rest assured the "video card"...
Although I don't really follow gigabyte mobos much, I can tell you that the Asus rampage 4 black edition is due to be either announced or released on October 29th, and honestly I'd take an Asus board over gigabyte any day :)
The black edition is their new x79 LGA2011 socket board.
Just to narrow things down a bit, what type of company is it? and what kind of inventory are you exactly looking to track, because different systems have varying benefits depending on the inventory being tracked.
AMD has yet to release an official price for the 290x, wait till tomorrow and you will know for certain. Anything you have read about the AMD 290 series is 95% speculation at this point as they have not released any information to the public as of yet.
290x prices are suppose to be released...
I'll leave the part suggestions to "Dangman" and "tiraides", however if you are set on nvidia graphic cards, hold off on buying it till the 28th as their introducing their "holiday bundle" and several additional features unique to nvidia graphic cards.
For your ram I would suggest these:
http://www.ncix.com/products/?sku=66354 $180
and price match them with this:
http://www.amazon.ca/dp/B006EWUO22/?tag=pcp0f-20 $130
http://pcpartpicker.com/ Is a good starting point as it connects you to more than one retailer.
Some of these retailers have price match (such as www.ncix.com) which simply requires you to place the part link you found cheaper at another site and they usually match it at the very least, and...
Hmm, I only suggested that since you only mentioned mild overclocking, but at same time If your budget is $2500(including shipping/tax or not) without including graphic cards into the equation then you can definitely keep the H100i.
Also note that suggestions on parts tend to change weekly, so...