for gaming performance is FX 6300 with RX 460 is better or A8-7600 , and if i combine a graphic card with the A8-7600 does this cancels the GPU in the A8 or it combine it's effort with the graphic card ?
Read this comparison. http://www.game-debate.com/cpu/index.php?pid=1980&pid2=1146&compare=AMD%20APU%20A8-7600%20Quad-Core-vs-AMD%20FX-6300
If you add a discrete card to your FM2 motherboard it will either cancel the R7 7600 and work alone or function as two cards IF and I stress IF, the videocard matches the R7. for example the R7-240. This is selectable in the motherboard BIOS setup. I advise you to read up on AMD Dual Graphics. There are specific youtube videos on this subject.
I would say just get a nice beefy vidcard and add it as discrete, of course that also depends on what you actually have already.
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