Hi , first thing I would say is change the PSU . The one you list is WAY over what you need . A 750w would be more than sufficient, specially in the RM range they are very good PSU's . Can't help you too much with the AMD kit , I am an Intel / NVIDIA man myself . But I would say think about 2 GTX 770 rather than the R9 280 as they run cooler and quieter . Double check the case will take the 240mm rad , pretty sure it will tho . If you can afford it go for the Samsung 840EVO SSD , great bit of kit , comes with Rapid mode , which makes it even faster . Good luck .
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