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Original post is at the bottom, newest update at the top. ;)

I didn't think to add this before, but you can download a 15-day trial of Modo for free if anyone want to try this for themselves. If you do try it, please take the time to report your results, even just to say there was no noticeable difference. Thanks! Here's the demo download page:

I'm going to ask Luxology if they can shed some light on the situation...

I was searching around for ways to improve graphics performance on OS X and I found an article about disabling an Apple GPU power management kernel extension (I checked and this is loaded on my Mac).

I also noticed that the same games run much better in Windows 7 under Bootcamp on the exact same hardware. These are OpenGL apps and do not use DirectX. Windows also runs much hotter. The case is hot to the touch and the fans run at their max 6,000 RPM pretty much the whole time Windows is running.

In light of these two things—the Apple GPU power management kernel extension and Windows performing better and running hotter—it looks like there is some software layer imposed by Apple that is reducing performance to keep the hardware cooler. -Edit: It seems the GPU power management extension only has to do with dual GPU models, so it wouldn't effect me. Still, it's obvious there's some software-level restraint on performance.

I have not yet tried removing the kernel extension because obviously running Modo gets the performance boost without removing it. There is still something simpler going on here that allows Modo to boost performance (without abandoning power management and melting the components :3 )

I've noticed that, with no other changes, Urban Terror and Second Life (both use OpenGL) will have double their usual framerate if I run Luxology Modo and use it to render a preview image first. I first noticed this effect a few years ago when I started using Modo. Without changing any settings, Unreal Tournament 2004 would be faster and render effects that just didn't show up at all before.

Any ideas why this might be?

Urban Terror, Second Life, and a fully-functional demo of Unreal Tournament 2004 are all available free online if anyone with Modo wants to try for themselves.

I'm still using Modo 301, but I imagine whatever they did to optimize performance has survived. I'm on a MacBook Pro 3,1 (this model only has one GPU; no dual integrated/discrete GPUs) running OS X 10.7.4 (though this was happening before Lion):

Hardware Overview:

  Model Name:   MacBook Pro
  Model Identifier: MacBookPro3,1
  Processor Name:   Intel Core 2 Duo
  Processor Speed:  2.4 GHz
  Number of Processors: 1
  Total Number of Cores:    2
  L2 Cache: 4 MB
  Memory:   4 GB
  Bus Speed:    800 MHz
  Boot ROM Version: MBP31.0070.B07
  SMC Version (system): 1.18f5
  Sudden Motion Sensor:
  State:    Enabled

NVIDIA GeForce 8600M GT:

  Chipset Model:    GeForce 8600M GT    
  Type: GPU
  Bus:  PCIe
  PCIe Lane Width:  x16
  VRAM (Total): 256 MB
  Vendor:   NVIDIA (0x10de)
  Device ID:    0x0407
  Revision ID:  0x00a1
  ROM Revision: 3175
Color LCD:
  Resolution:   1920 x 1200
  Pixel Depth:  32-Bit Color (ARGB8888)
  Main Display: Yes
  Mirror:   Off
  Online:   Yes
  Built-In: Yes
  Resolution:   1920 x 1080 @ 60 Hz
  Pixel Depth:  32-Bit Color (ARGB8888)
  Mirror:   Off
  Online:   Yes
  Rotation: Supported
share|improve this question
Have you used an app like GFXCardStatus to see if Modo is turning on your discrete graphics card while those other apps aren't (even if they probably should)? – LessPop_MoreFizz Jul 2 '12 at 5:00
As you can see, I have a MacBook Pro 3,1. It only has one GPU. Even if this were the case, I doubt a preview render in a 3D modeler would push me over the edge and a 3D game would not. – iynque Jul 2 '12 at 19:39
Strange, maybe it's because of faulty NVIDIA chip it contains. Something like 3D render will expand few contacts that are contracted or cracked normally. Just speculation. – iskra Jul 3 '12 at 9:59
I guess it's possible that it's a hardware problem. Regardless, I still want to know what the software is doing to fix it (and how I can apply the fix automatically without having to open Modo). I just have no idea how to even investigate such a thing. – iynque Jul 3 '12 at 18:03
To be a little more clear, I don't know why a 3D render would cause the contacts to heat up and expand if a more-intensive 3D game does not. There must be something about Modo specifically, not just intensive use. – iynque Jul 30 '12 at 2:04
up vote 0 down vote accepted

MacBook Pros come with dual GPUs (built-in Intel and discrete nVidia) and the OS switch between them in the background, depending on amount of workload. it is likely you went over the graphic intensiveness threshold with Luxology Modo and the OS switched from the low-end Intel GPU to the mid-range nVidia, which benefited other running 3D apps.

share|improve this answer
I included my hardware. You can see that I only have one GPU. My MacBook Pro 3,1 is from 2007. Dual GPUs were introduced in late 2008 unibody models. – iynque Jul 2 '12 at 19:41

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