Building an i7, need help getting the best deal

[cryzr]

I initially had planned on building an i5 but ended up getting a good deal on an i7 and motherboard so now I am going that route instead. What I have:

i7 920 D0 processor

Asus Rampage II Gene

Corsair 850 watt PSU

Acer 23" (1920 x 1080) Monitor

What my question: Now I am a little over budget where I would like to be but still want to end up with a nice machine. I can get 4gb of Gskill ddr3 PC16000 for $80 on craigslist but I'm concerned about only getting 4gb on a board with 6 ram slots (I read somewhere it is a better idea to go with 6gb and fill up 3 of the 6 slots).

I would also like to get a Radeon HD 5830 (or possible two 5750's).

Is it okay to get the 4gb RAM or should I bump up to 6gb and maybe get a lesser Graphics card?

(also I should note that I'm building this computer for dual reasons, one for gaming, and two becuase I'm an architecture student and I will use it for rendering programs such as Revit and Microstation so I was wondering what will help the most for getting rendering times lower.)

 

[banthracis]

If you're rendering you should be getting a CUDA GPU.

i7-930 is the same price as a 920.

Don't need an 850W PSU. For 1 GPU, and some xfire setups, a 650 is fine.

If you're gonna go 1366, you should take advantage of triple channel.

Also, fill out form in sticky, link in my sig. Can't really help you more w/o more info, stuff like budget.

 

[cryzr]

Thanks for the template tip banthracis...

APPROXIMATE PURCHASE DATE: With in the next two weeks

BUDGET RANGE: $300 after Rebates for the Graphics card(s) and Ram (can be flexible if the suggestions call for it)

SYSTEM USAGE FROM MOST TO LEAST IMPORTANT: Gaming AND Rendering

PARTS NOT REQUIRED: CPU, PSU, Motherboard, Monitor, CPU cooler.

PREFERRED WEBSITE(S) FOR PARTS: No preference

COUNTRY OF ORIGIN: US

PARTS PREFERENCES: None

OVERCLOCKING: Yes

SLI OR CROSSFIRE: Maybe

MONITOR RESOLUTION: 1920x1080

ADDITIONAL COMMENTS: I already have the i7 920 (realize the 930 is the same price but I got it with the Motherboard for the right price). I know I don't need 850W PSU but I got it for the right price so it was a no brainer.

I'm not familiar with CUDA GPU's, how much better are they for rendering and will they be able to serve a dual purpose for gaming as well?