My recommendation is to go for a gaming PC even for game development. The reason is that a gaming computers usually offer exactly what it is that you need for development too, including a powerful graphic card and plenty of RAM. One that I personally like it Dell XPS 8700 (highly rated, see here http://www.consumertop.com/best-gaming-pc-under-1000/ for example). Also Cybertron PC 5150 Unleashed II is really nice.
components
Intel Core i5-3470 box (6 814), Gigabyte GA-H77-DS3H (2 975), HIS Radeon HD6770 (3 550), Xilence 480W SPS-XP480.(12)R3 (1 190)
Such components will make you feel comfortable)