Got some questions about your build, before I talk about the psu.

First of all, why 16GB of RAM? A bit overkill for gaming isn't it?

Also, why not downgrade your SSD so that you can fit in a 1TB HDD (trust me, you'll want a 1TB HDD with your SSD, you are not going to put all your unneeded files in a SSD...).

I would recommend you going with air cooling since it is a much easier system to deal with, as with liquid cooling, they can deteriorate over time and a bunch of problems could come out, resulting in water being all over your system (which will fry the stuff in your pc).

Also, with that budget, you could either go for a really good mid-tower case or a full-atx tower case (if you go full tower, I recommend the Phantek Enthoo Pro).

Now with the psu, 600 watts should be able to handle all of that easily. Not sure how much headroom you'll have though. But if you are planning on Crossfiring them (which it looks like), you'll want a 1000 watt psu to be able to handle them with ease and have a nice headroom.

But this is something I would have gone with to make it better.

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