Dolphin, the GameCube and Wii emulator - Forums

I have two GTX 460's in sli however I'm well aware Dolphin can't utilize sli. If I I lower IR to 1x with everything else on performance settings, unlock fps I can get awesome speed - over 100fps in SMG2 with occasional drops under 100fps. However when I use IR, typically anything above 2x it results in massive slowdowns. I can go from 90fps to 100fps down to 60fps to 70fps, sometimes lower which is a shame since it makes games look nice. My question is there anything I can do from my end to speed up higher IR's or something the devs would eventually be able to do?

My full specifications:

Core i7 950 @ 3.8Ghz
2x GTX 460's in sli.
6GB DDR3 Ram

I usually keep IR on auto (multiple of 640 x 528) using the OGL backend with AA off, AF 16x, EFB to texture, 1080p 16:9 fullscreen resolution, efb scaling on. The settings I use are balanced between performance and compatibility without sacrificing visuals. Typically games stay above 30fps (30fps games) and 60fps (60fps games) regardless of IR with the occasional hiccup/stutter that it will briefly drop the game below 30/60 fps. I thought with the massive performance boost Dolphin received higher IR's would've had less of an impact on performance.

Thanks. I searched but had trouble finding anything, I do vaguely recall similar topics on the subject in the past but can't seem to locate them now.

It's probably your processor more than your graphics cards; higher IR strains the CPU too! Super Mario Galaxy 1/2 are very demanding; and upping the internal resolution will push everything in your computer harder.

I can understand but that much slowdown? I think 2x is the max I can go before I experience significant slowdown and games look awesome with 3x, 4x or Auto but not worth losing much speed over. I wish I had a newer OC'd processor to see if that's the case with my gpu. What's the max IR the GTX 460 should be able to handle without slowdowns?

Btw with the JIT optimizations wouldn't it have theoretically reduced the cpu load giving more cpu time for other operations? If so how come there is still such a large slowdown with IR? It seems like I'm gpu limited, I originally thought my gpu would've been capable of IR's above 2x.

(11-23-2014, 07:19 AM)Xtreme2damax Wrote: [ -> ]I can understand but that much slowdown? I think 2x is the max I can go before I experience significant slowdown and games look awesome with 3x, 4x or Auto but not worth losing much speed over. I wish I had a newer OC'd processor to see if that's the case with my gpu. What's the max IR the GTX 460 should be able to handle without slowdowns?

Performance at higher IRs also depends on the GPU model / architecture and the backend used.

For example with any DX11-capable AMD Radeon card (HD5000, 6000, 7000, R7 or R9 series) using the Direct3D backend, the difference between 1xIR and 4xIR is much smaller.
With a modern AMD GPU, running Dolphin at a higher IR (2x or Auto IR) sometimes can be even faster (!) than using native res. (1x)

(11-23-2014, 06:46 AM)JMC47 Wrote: [ -> ]It's probably your processor more than your graphics cards; higher IR strains the CPU too!

Since when? I get exactly the same fps at 1x ir as 4x.

In a lot of games I do too. But not Super Mario Galaxy.

@Xtreme2damax Have you configured your driver to always reclock your GPU in performance mode? 2xIR should run very fine on this GPU :/ As it's SMG, I guess it's because of the async EFB access which ends in a CPU-GPU sync point.

@JMC: I don't think so. IR should have no effect on the CPU usage.

It doesn't affect CPU usage, but it does bottleneck some kind of CPU to GPU communication reliant on CPU speed.

Well it's not just SMG/SMG2 I get slowdowns in and experience slowdowns with higher than 2x IR in games that don't utilize cpu efb access and other compatibility options. It's true slowdowns are worse in some games than others.

Gonna check how many fps I lose between different IR's.