AMD is releasing a new salvo of mainstream graphics cards today that should fall in the sub-$80 price segment, dubbed the Radeon HD 4670. The GPU at the heart of the 4670 is based on the same RV770 architecture used on the Radeon HD 4800 series, sans a few stream processors, ROPs, and other assorted elements, but with what is essentially the same feature set as its more expensive counterparts. We've got a couple of these new cards on hand and plan to show you what they're capable of on the pages ahead. After reading, you may be surprised by what 80 bucks can get you these days...