I'm not sure which clock is the nothbridge in my bios. Seem tot use all kinds of different names compared tot most mobos i've seen. But on page 96 you can see all my bios settings. Looking at you resolutie (triple monitor) more gpu is always nice though like In said before i dont know of the cpu Will be able to use that power. Beside that I really dont know what frame you Will get now on a 1080 maybe nice to research (?) I assume you use 60Hz (?) So that may determine your choise? Looking at it from a economical perspective "frames will likely get cheaper every generation" (of you understand what mean?). So that might be a reason to go for a cheaper gpu because in the future you will probably pay less for each frame (if that makes sense?). But this theory is depending a lot at improvement and competition which needs to be as strong as if now is regarding AMD/Nvidia to make cheap frames and does not take in consideration the 2e hand value of you gpu. I'm don't have the knowlage to say for certain which gpu Will hold the best value over time. I suspect the cheaper one because of can loose less value although i've seen in reality that "legaxy" of a card can mean it keeps it's value better.
Though the last economical points arent really Clear because i cant predict the future (my glass ball stoped working today). It MIGHT (???) help you choise at least it did my best trying to look at a few possible views.
I hope it is usefull information. (Sorry pretty long
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