I am going to build a mid-tower desktop for video editing and want to keep the price under $1K. I already have monitor, keyboard, mouse, printer, external HDD. I am leaning toward the P5Q3, because of the DDR3 RAM, but I'm not sure about the GPU. It states it is Crossfire ready, but I only plan to use 1 card and I prefer nVIDIA. Maybe I need to choose a different MB or maybe the Radeon 4870 will do me OK. Any Ideas?
I think when considering a video editing machine, you should consider the following (in this particular order):
Support for multiple high-speed hard disks
Read/write speed of hard disks
Amount of RAM
Ability of video card(s) to drive multiple displays.
In other words, your first priority should be your video cards, but on getting a mobo that can support high-speed HDs. That's what you'll need first for a responsive video editing experience. Hope this helps!
A 4870 is for gaming. You'll be working mostly in 2D. You can always try a motherboard with integrated graphics like a G41/45 chipset and add the card later if you need to.