GTX 690???? no no no... let me quote something that was voted as best answer in an older thread
Not sure if you've already purchased your 690 or not but I will say my share anyway.
I was in the same situation as you. So I went ahead and ordered both. I had a 690 and a pair of 680s in my house. In the end I stuck with the 680s SLI. A few reasons as to why.
1. Heat. Many people think you'd get less heat with 1 card vs two. In this case you don't. The 690 gets pretty hot. As does 680 SLI. Big difference between the two? How the heat is moved. With the 690 heat will exhaust inside of your case. Your case will get very hot. Temps raised inside my case by about 10C with a 690. All because it was exhausting all that heat inside of the case. Sure, my pc could handle it. But either way it's not good for everything inside. That alone was enough to make me not want to keep the 690.
2. Future proof. In the end it's cheaper t buy two 680's and enjoy them for all they are worth. Once it's time to upgrade. Throwing another one in shouldn't be a problem. I don't have to fork out another 1k. I'm sure by then. Whatever knew card were coming would most likely make the 690 feel dated or at least not worth another one.
3. Resale Value. There is going to become a time where I don't game as much. Or maybe I'll end up seeing SLI as overkill. With 680SLI I will be able to sell one of the cards and keep the other inside my case. So I'll still have a GPU if I need it and not lose everything. Also, people are willing to spend less when used. Not more. So it's going to become a lot harder to sell a 690 in the future.
4. What If A Card Breaks? Lucky me. If I had two I could use one while the other gets fixed. 690 craps out. You'll be waiting a while for the fix and be out of a GPU.
In this case the positives just don't out weigh the negs. Is the 690 the sexiest case to date? You bet! Does it have pros!? Sure. Less power and 1 PCI slot. Also it runs on PCI 3.0 even if your running a SBE.
But it also isn't as fast as 680 SLI. Pay the same for less speed? The power difference isn't huge. I'm willing to bet anyone spending that much on a GPU would have a decent GPU to begin with. 680 SLI has more connections. Looks sexier in a case. Fills it up more vs 1 card.
In short. I'll say this. Get a 690 only if you plan to buy another one in the future. IMO that's its only selling point. You'll be running quad SLI with only two slots taken. If you only plan to run 1 690 then I see no point in getting one. As 680/670 will work better and keep your case cooler.
Hope that helps.
P.S- With the 690 you must have the connections in a certain order to be able to use all 3 monitors and max 3D performance. I wanted to use all DVI ports on the 690 for 3 monitors. What they don't tell you. In order to max your performance on a 690 you must use the display port. I just spend 1000K on a GPU. Didn't like the idea of being forced to buy an adapter just to enjoy it.
That being said i think you should rule out the GTX 690, now lets rule out the GTX 680's .....
They say a picture is worth 1000 words so i am not going into details about the GTX 680 vs GTX 670 in SLI.... it will be up to you to decide if the extra 200$ in the GTX 680 sli are worth it or not:
ok...let's move on:
CPU:
I'll get to the point by saying I'm looking to build my own high-end gaming desktop
If that's the case then drop the i7 3770k and pick a i5 3570k, in gaming, they performs exactly the same and if you turn on the HT (turbo mode) in the i7 the performance will actually decrease while you game so unless you're planning to do some HEAVY video editing and transcoding the i7 is only going to be an unnecessary and useless expense.
Ram: again... for gaming only 4GB are needed, 8GB is the norm today simply because its VERY cheap, get yourself a 1600mhz 8gb kit and you will be ready to pwn noobs in no time
SSD: my recommendation (if you have the money) is to get a 240-256GB ssd like the Crucial M4, Samsung 830, Vertex 4 or Mushkin chronos deluxe... if your budget doesn't allow that then get a 128GB SSD of the same model as the ones i listed above.
HDD: as a storage drive all you need is space...the amount is up to you, pick up the cheapest 7200rpm drive you can (WD, Samsung or Seagate ONLY)
Power Supply: for a GTX 670/680/7950/7970 SLI/Crossfire setup the recommended wattage is 750w... buy the
Corsair HX750 ... inexpensive, reliable and efficient are the three words i would use to describe that PSU
Optical Drive: do you need blu-ray??? are you really going to use it?? if you answered those questions with a "yes" then buy a BD drive.
Motherboard: Buy an Asrock Z77 Extreme 6-.
Case: IMO...the best case ever made to date is the NZXT Switch 810 its simply PERFECT in every way!!