Building a new computer, need advices.

1) an i7 is a poor choice for a game rig, but perfectly fine if doing productivity work (audio/video editing or other content creation). More likely than not an i5 or an 8 core AMD would be the better choice because modern games cannot use Intel's HT cores, and next gen console ports SHOULD (but no guarantee) be able to make use of all 8 AMD cores. For video editing you can expect 0% performance increase from an i5 to an i7, and a 20% decrease in rendering time for productivity work. If that 20% is worth the extra $100 then go for it, otherwise just stick with the i5 as it will run cooler and typically OC better.
If you have the money to burn then consider a 6 core Intel LGA2011 platform. This will give you some added physical cores for future games, and also be a dream to do editing with. If only gaming, then it would not be worth it, but as you do some editing then it is something to consider even if it is overkill. Just note that you would need a different CPU and motherboard, and you would want to have 4 RAM modules (4x2GB or 4x8GB) if you go this route.

2) Sabertooth is a pretty board, and they work quite well, but if you need to cut any budget then know that you can get a much cheaper $150 board with 90% of the features and 99% of the performance. Otherwise, solid board and if I had the money to burn then I would definitely consider burning it on one of those.

3) Solid GPU. A GTX 770 will be much cheaper but capable of OCing to nearly the same performance. Also, keep in mind that GDDR6 is supposed to come out this year on AMD cards. If that is something important to you then consider getting a slightly cheaper card today that can still game, and then upgrade when the new cards come out this spring. nVidia cards may or may not have GDDR6 this year as AMD is spearheading the technology and will get it first.

4) Great case. One of the few I would consider upgrading to in the future from my CM690.

5) Why spend all of the extra cash on other parts and cheap out on the Ram? Corsair and G.Skill are both good cheap gamer ram with few failure rates, but consider something faster like a DDR3 1866 with CL9, or 2133 with CL10 for a bit better performance with a minimal price increase. Don't get any Ram modules smaller than 8GB. 2x8GB is exactly what you want for a game rig.

6) for the PSU just make sure that it is 80+ Bronze or better, and that it is rated to be used for Haswell processors (most of them are now). Corsair is a solid brand, and would match your case, but Seasonic, EVGA, Silverstone, and Antec are all decent. OCz was also not bad after they bought PC Power and Cooling, but as the company is now bankrupt I would avoid their products under both brand names simply as a support issue. 600W should be plenty of power for your setup with a few HDDs and SSDs and a single GPU, but consider an 850W if you think you may add a 2nd GPU in SLi down the road.

7) That case has plenty of space for fans, but you may find that you probably won't need them unless you are in a warm climate, or are OCing the system to the moon.

8) For the SSDs look for the Samsung 840EVO. If you have a lot of games then spring for the 512GB drive so that you have space to put games and your scratch disc for video editing. Video content should live on a nice fat HDD.

9) For HDDs, especially as you are doing video work please hear me out from a fellow video editor: Hard drives fail. It is what they do best. It does not matter what drives you buy, they simply die at the least convenient time possible. Get 2 large HDDs (2-4TB) and put them in a RAID1 array so that if a drive dies then you have a good chance at not loosing any information. The onboard Intel RAID works pretty well for this and will still pass TRIM commands to your SSD when in RAID mode. As a part of going with a RAID array, avoid low RPM green drives... they do not deal well with the timing required by RAID as their performance is inconsistent. WD blue, black and red drives are all good for RAID, and most Seagate drives (what I use) work well also.

Hope that helps!