For Blender, Vegas and Gaming- AMD or Nvidia?

[TheyCallMeGunny]

I'll admit up front I'm a bit of a Nvidia fanboy. But facts stand that Blender/Cycles simply works best with OpenCL, which means that AMD cards are the best route to go when using it.
However, I also use Sony Vegas nearly everyday. And Vegas gets a nice kick from Nvidia's CUDA cores.
As for gaming, I have a personal bias in that I love Nvidia. But really for gaming, either works.

So my question is this: How considerable is the performance increase with AMD/Blender versus that of Vegas/Nvidia? In my experience, Blender BY FAR takes longer to render, so that's where the increase is most needed. But if Blender's render time is only reduced (hyopthetically) 20% by using a specific AMD card, while Vegas could be dropped say 70% with a Nvidia (or vice versa), then that will be a large factor in my decision of where to upgrade.

I am saving up for a new CPU and Mobo, actually saved every penny of my last paycheck, so when making your recommendation please try to use the following specs instead of my signature's components:

CPU:

Intel Core i7-4790K Devil

[ccokeman]

Thats one hell of an upgrade. I would go with what you use the most and you wont go wrong.