Weird bottleneck issues, getting more fps at 4k than at 1080?

[promo25]

I recently got a great deal on a R9 fury nitro, but I have a weird problem.

My CPU should be bottlenecking it since it's an old FX 8120 overclocked at 4Ghz, but none of the cores reaches more than 70% while playing GTAV for example.

I don't get 60 frames with everything in ultra on 1080p but I get a 10fps increase if I set the GTAV resolution to 4k after enabling oversampling on the AMD drivers. I have a 1080p monitor so there is no visual difference, only fps increase. Why does this happen? It should run worse at 4k and better at 1080p.

I checked the CPU usage while playing and it's 4 cores at 70% and 4 at 30%, I thought when you were at 90% or nearby it meant that you were bottlenecking but it seems like there is plenty of room for the game to use more cpu.

My previous card, a 6950 was always at 100% and CPU was around 60% so no CPU bottleneck. The R9 Fury usage goes from 1% to 100% then 70% then 12%, pretty unstable so I really have no idea of what's going on here. Is it really a bottleneck or is there something wrong with my card/drivers/other hardware like the psu or ram?
Thanks

CPU usage:

GPU usage:

System:
AMD FX Series FX-8120 3.1Ghz OC @ 4Ghz
Cooler Master GX 750W V2
Heatsink Noctua NH-U9B SE2
G.Skill Ripjaws X DDR3 1600 PC3-12800 8GB 2x4GB CL9
Asus Sabertooth 990FX AM3+
Sapphire R9 Fury Nitro OC 4GB HBM

 

[Barty1884]

Bottlenecking doesn't necessarily need to be maxed out on GPU or CPU and nowhere near on the other. That's the most common scenario, but pairning a really strong GPU with a mid-level CPU can see neither hitting close to 100%.,

At 4K your R9 Fury can 'take over' in certain situations, limiting the CPU's use - but not consistently. In essence, the R9 Fury is doing all/most of the work at 4K in some situations/scenes, but when the CPU is called in to do it's job, it can't keep up.

 

[promo25]

Bottlenecking doesn't necessarily need to be maxed out on GPU or CPU and nowhere near on the other. That's the most common scenario, but pairning a really strong GPU with a mid-level CPU can see neither hitting close to 100%.,

At 4K your R9 Fury can 'take over' in certain situations, limiting the CPU's use - but not consistently. In essence, the R9 Fury is doing all/most of the work at 4K in some situations/scenes, but when the CPU is called in to do it's job, it can't keep up.

Thanks, this makes sense. What can I do to increase the CPU performance? I could overclock it more if I had watercooling, will the performance increase enough to keep up with the fury if I overclock it to around 4.5-4.7Ghz? Is there any AM3+ CPU that will not be bottlenecking with the fury?

 

[bailojustin]

on 4k, do you have the game running in 4k resolution aswell? and what are the graphics settings in comparison? both 60FPS? V-Sync? Triple Buffering?

 

[Barty1884]

Thanks, this makes sense. What can I do to increase the CPU performance? I could overclock it more if I had watercooling, will the performance increase enough to keep up with the fury if I overclock it to around 4.5-4.7Ghz? Is there any AM3+ CPU that will not be bottlenecking with the fury?

To improve your CPU performance, the only option would be to OC it further with a decent cooler (you could do it on high-end air like a NH-D15 too, so liquid isn't the only option), but you'd need a bit of luck on the motherboard too for a quality OC - I don't know too much about that board. There's no AM3+ CPU I'd recommend upgrading to. A stable 9590 would get you closer, but requires one of a specific (and small) list of motherboards that truly support it - and that's a heck of a $$ investment to get you 'closer', but still not very 'close'.

You would need an extremely strong OC to pair equally with a R9 Fury (like, record-setting OC!!), but the more you can do to the CPU, the lesser the performance impact will be.

 

[bailojustin]

Also, are your CPU cores parked? IMO it is very important to unlock your cores, especially with the FX processors.

 

[Barty1884]

Also, are your CPU cores parked? IMO it is very important to unlock your cores, especially with the FX processors.

Considering the first image shows 8 cores with activity on each, I don't think it's a cores parked issue.

 

[promo25]

Thanks, this makes sense. What can I do to increase the CPU performance? I could overclock it more if I had watercooling, will the performance increase enough to keep up with the fury if I overclock it to around 4.5-4.7Ghz? Is there any AM3+ CPU that will not be bottlenecking with the fury?

To improve your CPU performance, the only option would be to OC it further with a decent cooler (you could do it on high-end air like a NH-D15 too, so liquid isn't the only option), but you'd need a bit of luck on the motherboard too for a quality OC - I don't know too much about that board. There's no AM3+ CPU I'd recommend upgrading to. A stable 9590 would get you closer, but requires one of a specific (and small) list of motherboards that truly support it - and that's a heck of a $$ investment to get you 'closer', but still not very 'close'.

You would need an extremely strong OC to pair equally with a R9 Fury (like, record-setting OC!!), but the more you can do to the CPU, the lesser the performance impact will be.

Well I guess I can wait for Zen and if they're good for gaming get one. If it sucks I'll have to go with intel :/

 

[Barty1884]

Yeah, now is not the time to be upgrading. Wait for Zen. Hopefully it offers competition. It might be cheaper/equal performance, or it might force Intel to lower prices etc.

Either way, even if Skylake/Kabylake is the way to go, it won't be any more expensive in a couple of months.

Until then, I'd just suggest you OC the 8120 as far as you can, stable. Investing in something like an NH-D15 wouldn't be a bad idea to accomplish this, and you can always move it to a new build when the time comes.

 

[promo25]

Yeah, now is not the time to be upgrading. Wait for Zen. Hopefully it offers competition. It might be cheaper/equal performance, or it might force Intel to lower prices etc.

Either way, even if Skylake/Kabylake is the way to go, it won't be any more expensive in a couple of months.

Until then, I'd just suggest you OC the 8120 as far as you can, stable. Investing in something like an NH-D15 wouldn't be a bad idea to accomplish this, and you can always move it to a new build when the time comes.

Will that noctua or other coolers work with AM4? Because unless its the same size as AM3+ I'll need special brackets or something.

 

[Barty1884]

I haven't heard much for AM4 and a new socket layout, but Noctua are the people to go with - even if there is a new socket, Noctua will send you the mounting brackets:

We provide mounting upgrades for Noctua CPU coolers free of charge, so if you would like to continue using your Noctua cooler on a new socket, we will send you a new mounting kit at no additional cost. For ordering our mounting kits, a proof of purchase (photo, scan or screenshot of the invoice) of both a Noctua CPU cooler and hardware components corresponding to the specific kit are required.

http://noctua.at/en/support