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Even tho I've heard they're similar and both have 4gb of vRAM now, I saw a test where the results had a decent boost just from the CPU having more to work with since the video card was the upgraded model. Hardware is a balancing game, gotta make sure you don't bottleneck other places because a small upgrade could make a huge difference. I personally would prefer baseline across the board (except RAM) but after seeing that test I may max the video card.
 
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