I’m confused, Fortnite at ultra low. Will it bottleneck yes or no
For me, Fortnite is a difficult game to give advice on because it has been updated A LOT and has different modes (e.g. DirectX 11, 12) and loads of features you can turn on/off for eye-candy.
I normally rely on performance reviews like this:
Counter-Strike 2 is available now, with improved graphics powered by Valve's Source 2 engine. All the maps have received overhauls, which gives them a much more realistic look, without breaking the classic CS Experience. In our performance review, we're taking a closer look at image quality...
www.techpowerup.com
and this:
Thermal Grizzly: https://www.thermal-grizzly.com/produkte/522-cpu-contact-frame-for-12th-gen-intel-by-der8auerSupport us on Patreon: https://www.patreon.com/...
www.youtube.com
But, I don't know of any reliable sources for Fortnite which can show you performance at different resolutions and graphical settings.
So... we're left with searching for YouTube videos to try and assess performance, like the one tamzzy linked you earlier and anecdotal evidence like Gary* has shared with you.
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From what I can gather in the YouTube videos and from what Gary* has shared, if you use performance settings than you will hit a CPU bottleneck fairly easy in this game, even with an entry-level GPU.
I would imagine that you want
at least the 200 fps that Gary* has reported, so we can safely say that a 5600 non-X or 5600X is the baseline you should aim for.
The next question is, at which point is the CPU enough? I don't know the answer to that question, perhaps
@Gary* can share his utilisation % for CPU/GPU.
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Realistically, I doubt you're going to get a much better CPU than the 5800X if you want a 6800 XT in the used PC, so the question is: do you drop lower than the 6800 XT to fit a better CPU?
From a quick reddit browse, it looks like there are mixed reports and it maybe depends how intensive the games you play usually are.
This comment suggests a 6800 XT is too much and you should drop GPU DOWN and the CPU UP:
lmao my fps went from like 200 on performance mode with 6700xt and 5600g, to 600+ average with a 7800x3d and the same 6700xt
But, that's just one comment and the 5600G is slower than the 5600X or 5800X (the G models have half the cache).
If the 7800X3D makes that kind of difference, I also don't know if that is because of the X3D's cache, or because of the RAM speed and the first comment in that thread says that upgrading to a 5800X3D did
nothing for their FPS.
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My answer to your question: I don't know, but I suspect you'll be bottlenecked by the CPU.
Would I drop down from the 6800 XT? Personally: no, there's not enough confirmation it would be worth it, but if maximum FPS is very important to you (e.g. competitive gamer) then I'd recommend you look into it more than I have.