7850 GPU bound in Tribes: Ascend, but overclocking doesn't improve FPS

[soccerballtux]

this is the first I've seen this before, I'll have more testing later.

core: 900mhz, 48fps
OC: 1150mhz, still 48fps.

new monitor (1440p). Memory bandwidth bound? Overclocking 1200->1250mhz did absolutely nothing (not even 1 extra FPS), also it's highly unlikely I'm memory bandwidth bound

any thoughts?

 

[KingFatty]

What about going the other way - if you decrease the GPU core speed, will fps drop?

Have you ruled out a CPU bottleneck?

 

[soccerballtux]

What about going the other way - if you decrease the GPU core speed, will fps drop?

Have you ruled out a CPU bottleneck?

that's an interesting idea I'll try that.

it seems odd to me to have a resolution dependent CPU bottleneck. I guess I'll re check everything. Also, the gpu was at 100%...I don't know much about gpu architecture these days but I thought it might be ... I don't know what I thought it might be, maybe a vertex bottleneck but not a shader one or something. only <1GB vram utilization too...

 

[soccerballtux]

ok it looks like I was hitting right up against the limit at 1200p
http://www.techspot.com/review/522-tribes-ascend-performance-test/page3.html

I'm kinda surprised it's such a heavy game. maybe it's just the resolution?

 

[Stuka87]

My guess is that game is poorly threaded so you are only using one or two threads, meaning you are CPU bound.

As a test, drop the resolution down to 720P, and rerun the test. If FPS is close to the same, its your CPU.

 

[soccerballtux]

looking at the scaling, it's actually spot on for the resolution. 2560*1440 = 3,686,400 pixels, which is 60% more than 1920 * 1200 = 230400;

and 39fps (at 1440p) divided by 0.6 is 65 fps...which is basically exactly what the 1200p is pulling. Makes sense considering AMD cards typically scale better with resolution than NVidia's

Interesting!