My boss bought new comps recently. The comp which i'm using now is fast like crazy.... If you want, I can take a look tomorrow and write you the spec. Its price is not above 1k eur...
Choosing graphic card depends on the type of rendering. There is CPU rendering and GPU rendering. CPU rendering demands processor and ram. GPU rendering demand something like quadro graphic card.
Some render machines like "V-Ray LT" are GPU oriented, but many other (including basic V-ray, Mental Ray, default Revit renderer) are CPU oriented. In my humble opinion, it is much better to choose CPU rendering because you need a good processor anyway, You will be spending money on that either way. The question is, will you be doing raster image processing anyway. You will use vector processing most of the time (or at least untill you learn to use Revit). So, don't be worried to much.
Visit BOXX . For these things, its a very good place to find some general info. Don't get scared when you see prices. For example, you can try to find much older Quadro card. It will fulfill what you need. Yeah, its not the newest, but hey, Quadro is still Quadro.... If some older model was one of the best cards for rendering 5 years ago, then I don't see a reason why it cant serve today. You can find a good quadro card for like 200 eur, you just need to dig....
Andrej Ilić
phonetical: ændreɪ ilich
MSc Arch
Autodesk Expert Elite Alumni