Nor do I, to be honest. When I had the cash to put down on a gaming PC, I just shopped around for the highest-rated in the 300 range, but since that's not an option for you... well, maybe go to google and type something like, "graphics card comparisons" or whatnot? I'm sure there are charts comparing Radeon to GeForce all over the web.
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K | H | A | Q | Q | A | H | K
"we're about 50 years behind the rest of western society." -icon on B8