Upgrading from the HD 7870 - R9 390, 290X, or 970?

Colin Hollenback

Distinguished
Jun 28, 2014
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Hey guys :)
So I recently bought a pre-built PC from my uncle (meaning it's a little older) as a baseline of sorts. I decided that I want to upgrade the graphics card to something that will assure I can run all modern games at 900p (eventually 1080p) on the highest settings. With the releases of the 970 and R9 390, I've been torn between the two - and any advice would be appreciated. Thanks!

P.S. Would the FX-8310 bottleneck any of these?