Low GPU usage low FPS, High GPU usage high FPS

Ne0Wolf7

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Jun 23, 2016
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Hello everyone,
Dispite my okay hardware (16 GB RAM, Xeon E3-1231 V3, GTX 950), I manage to pull out some pretty mediocore FPS on... minecraft.
I know it's a poorly optimized game, but I run it with optifine which is ment to optimize it.
To see if something was horribly wrong with my hardware, I ran NZXT CAM on another monitor and found that my hardware all had low usage, most notably the GPU.
CPU and RAM usage was all but constant, and the GPU was mostly low, but in the few times I did reach FPS that made sense, it was higher, but it was ever at 100 percent, maybe 60 percent max.
Also, when doing something you would think is less graphicaly taxing (like say, staring at the wall for no reason) my GPU usgage and FPS skyrocket. However, when doing something that should be harder for the GPU to pull off (like looking into the distance with maximum render distance and all the setting maxed out) usage drops to the twenties and FPS fall with it, also into the mere twenties.
I have tried a clean install of the latest drivers (might rolling them back help?), optimization mods, reinstalling the game, raising settings in Nvdia control panel to "trick" the GPU into full usage, seting power to "prefer maximum performence", and even overclocking (I hold 100th percintile for GTX 950's in user bench now :wahoo:), but it hasnt helped.
Good to note is that it works fine on servers (although theres much less to render there) and the drive its installed on only has 35 GB free (could that cause all this?)
I am at a loss... hanks for suffering though that post.
 
2 things to check
Open Nvidia Control Panel.
On the left click on Manage 3D Settings.

Under power management mode.
Choose Prefer Maximum Performance.

Under Threaded optimizations choose ON.

If that does not fix it Download DDU and install it with a desktop shortcut. Uninstall drivers in programs/features.
Reboot into safe mode.
Run DDU.Reboot into regular windows.
Install drivers and redo the above settings changes.
try your game again.
 

Ne0Wolf7

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Jun 23, 2016
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I had alrady done the first part, but even after using DDU I have the same problem. In particular this time, when I looked at the sky in such a way it was the only thing on my screen (the sky is literaly one solid shade of blue) my GPU usage was 96% and my FPS nearing three hundred, but when I aculay started to render the world and see stuff, my GPU usage droped to 30 percent and my frames to 30 FPS.
 

Ne0Wolf7

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Jun 23, 2016
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I found my problem, it was a CPU bottleneck.
I forgot that minecraft is a single threaded game (I sure hope they change this and the API is uses eventually) so when I looked at CPU usage and I saw such low usage, a single core/thread was actually maxed out. I checked it with HWiNFo, and sure enough, on thread was always hovering around 95-100%.