<$1000 non gaming build

Add Z77 chipset based motherboards to the mix: native USB3.0 (not worth it IMHO)

Basically, you have to ask yourself: what is more important, speed on SolidWorks or speed with the video editing?
If video editing, go with a consumer card: AMD Radeon HD 7850
Otherwise, if you're ready to spend on a workstation graphics card, go with the most expensive FirePro or Quadro you can afford (entry level FirePro starts at ~100$, not that I would suggest it...)

I would suggest an Intel i7 build (as video editing and 3D CAD both employ hyperthreading). But before that, a little word on overclocking.

Overclocking used to be difficult, but it's not anymore. With a simple change of the multiplier, my i5-2500k went from 3.3GHz to 4.1GHz (beyond that, I needed to play with my ASUS P8Z68-V LX's VCore offset settings). The reason I'm saying this is because it makes quite a performance difference, and if you want a quiet build, you're better off with an aftermarket cooler anyway.

That said, to decide between a more solid GPU vs. an Intel i7 processor, you need to see, used with your applications, which one makes the greater difference. If you choose the GPU, then go with an i5-2400 instead of the i5-2500. Personally, since it's not a gaming build, I would go with an i7-2600k and an AMD Radeon HD 7850.

Intel i7-2600k (newegg special 300$, it's quite a steal!)
CoolerMaster Hyper 212 EVO (~30$) + Arctic Silver 5 thermal paste (~10$)
ASUS P8Z68-V LX (~115$)
8GB Corsair Vengence Low Profile RAM CML8GX3M2A1600C9 as suggested by 87ninefiveone (~55$)
AMD Radeon HD 7850 (brand of your choice) (~260$)
Corsair TX650 as suggested by 87ninefiveone (~75$)
Mushkin Enhanced Chronos Deluxe 60GB SSD (~85$)

Total: ~930$ + tax + shipping - rebates
---no case, mouse, keyboard, speakers, OS, optical drive, storage drive---

Pretty solid if you ask me