Ok this will be like my 3rd computer I have built although this will be the first one in 5 years as my previous one has managed to last 5 years. Ive spent the past year browsing the internet and researching on the whole build. There has been alot of thinking gone into this...
The specs are as follows: CPU: Amd FX 8150
GPU's: Crossfired HD 6850's (2GB Version): Total: 4GB GDDR5
Motherboard: Asrock 970 Extreme 3
Hard Drive: 1x1TB (7200RPM), 1x500gb.
Ram: 16gb DDR3 1600Mhz
I've come across a problem though when choosing out the parts, the problem is the PSU, I've used online PSU Calculators and they say that 750-800w should be enough although the graphics cards specs are 500w each.
Well first I would like you to edit your post so that we can help you out better. There is a stickie at the top of the forums where it shows how to Ask for advice. The information from that post is needed to help assist you better.
With the limited information i have dont know what your using your computer for i will say this for a 6850 and 850W psu is overkill, if you dont plan to SLI for whatever it is your doing go with a 650W, if you do plan to SLI go with a 750W