Ok, then I'm clear that I'll get an asrock!
The truth is that I've noticed that quite a few people here have an asrock, there must be a reason xd
Regarding the graphics card, I'm still not entirely sure about buying a gtx680, I know it will last longer than the gtx660 but there's a minimum difference of 100€ and with that money and within a year, year and a half and another 100/150€, I could buy another mid-high range graphics card (a gtx760 for example) or even another gtx660 and set them up in SLI.
Because 2 gtx660Ti would be equivalent to a gtx680 or a gtx690???
Two 660ti are equivalent to more than a 680, anyway if you want Nvidia they are expensive, although depending on the model, the one that is cheapest is the Zotac and I'm not convinced by that dissipation for SLI and even less if the card doesn't have much separation between graphics.
Maybe a 670 would be better and since it's not long until new cards come out, you could buy another one later on sale, for 1080 you'll be able to play well although some games won't run at full speed, it will run with good graphics quality.
In two months I think there will be lots of second-hand 670s for sale and the new ones will also go down in price, the 660Ti although it has 2Gb of memory actually uses 1500mb, it's a bit of marketing the 2Gb thing, the 670 would use it since it has a 256-bit bus, in fact they should already start selling second-hand 670s given that it won't be long before the new series comes out.
another option if you have a graphics card is to wait a month or two, build the computer and put in graphics cards with the new series that should come out in March it seems.
To have 2 graphics cards attached, these models are usually better, although the 660Ti are also fresh but in SLI it will depend on the ventilation of the case.
http://www.pccomponentes.com/zotac_geforce_gtx_670_2gb_gddr5.html
regards