I was a civil that went to construction side to be an estimator, designer, model builder, construction engineer for an excavation company. I run a P2200 and only have a few issues from time to time. It seems to happen when there is a zero point and it drafts 2600 contours, or if the design engineer supplies what I call a "hyper mesh" for a big project when we have 1M+ triangles. I often use Civil 3D and Carlson Takeoff (integrated ACAD) simultaneously and have an existing surface, design surface(finished grade), and subgrade in 3D view simultaneously between the programs and have taken it up to 80% usage before. I view many CAD surfaces over 120 mb and do fine, lag occurs due the processor. I've never had a total crash due to the video card, worst that happens is that CAD turns hardware acceleration off and its hit or miss whether it'll let me turn it back on or restart the program.
You should be fine with it. Yes, gaming cards will work, but they are usually much louder, use more power, and generate more heat and heat is a workstation killer over time. I do much more 3D viewing now as compared to my engineering design days. I really don't think most people get the full use in CIVIL 3D from these 8GB+ cards and start falling into the realm of diminishing returns. Put the money towards processor speed and/or ram. I'd say that card will take care most CIVIL 3D needs.
Late response, but I'm bored and taking a break from the grind.
