Is 280x cfx worth it?

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I think it depends on what sort of performance goals you have. If you are running 1080P 60hz, 2 280X may be overkill. If you are running 1440 or more and or 120+ hz then a second card would give you a huge increase over a single 970 and probably a 980. However, as you said required a PSU upgrade. For that I don't know if it is really worth it. What PSU do you currently have?
I think it depends on what sort of performance goals you have. If you are running 1080P 60hz, 2 280X may be overkill. If you are running 1440 or more and or 120+ hz then a second card would give you a huge increase over a single 970 and probably a 980. However, as you said required a PSU upgrade. For that I don't know if it is really worth it. What PSU do you currently have?
 
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