http://pcpartpicker.com/parts/partlist/$1656.xx
High end i7, rates very high on just about any speed test
Motherboard isn't the highest, but its a good mid range mobo and much cheaper than a sabertooth or similar
For the design side, a 250gb SSD, big enough to install Windows on, as well as your editing software, with enough room left over to do your projects
Why 3 hard drives? That is to do a raid 5 stripe, which will give you better read/writes but also add a redundant layer, which works in that if any single drive fails you can still access all your data, replace the bad drive, and the array will heal itself, extremely versatile and great for backing up those important CAD projects or whatever
I did add an aftermarket cooler and past, the extra <$30 is worth it to keep your processor running cool
You may want to add a few extra fans for the case, but you can decide that once you get it all if you want
Went with an 850w full modular PSU, the price is a steal at $109 as you don't find much cheaper until you are around 550-650 watts and that would be cutting it close
Monitor isn't a $600 quad HD but it is a nice monitor at a higher resolution, and 25" is a nice size (I have a 27 and it works pretty well, but can be a bit large)
With extra fans that should put you right at $1700