To clarify, when you render and choose an AVC template, then choose ' Custom ', you have the option to render with GPU, CPU or AUT0.

I have yet to see anyone post that they have achieved any significant improvement using the GPU.

My CPU utilization seemed constant whether I had it on or off, and the render time for RenderTest remained the same.

http://www.sonycreativesoftware.com/forums/ShowMessage.asp?ForumID=4&MessageID=733950

Thank you very much, after you explained where the "Encode Mode" option was located, I found it and it made sense. I usually encode to mp4 using MainConcept codec, so never looked the Sony Codec.

thanks again, I'll share my results if I run the test,
Rich

Stringer, John Cline posted a couple of days ago that on an Intel Quad core cpu (few years old) a modest CUDA card achieved 30% better results. That's pretty good for that CPU and a $130 video card. I have a similar card and it was a tad slower to render than my new i7 950.

I also have an old Quad Core Q6600 similar to John's. With my GTX 260 I see no improvement in rendering times and the GPU usage is at 5 or 6%. However with Premiere Pro I see vast improvements in rendering speed with GPU usage up around 80/90%. I just dont understand why I am seeing no improvement in Vegas using the SONY AVC codec.

This has been covered here before, but since the topic is pretty confusing, it's worth summarizing it again:

1. No matter whether you can use CUDA for a particular operation, one hardware component will always limit performance ("bottlenecking"), It could be the CPU, the GPU, the RAM or the storage subsystem. The bottleneck may vary from one piece of software to another. Thus, it makes no sense to buy a fast GPU and pair it with a slow, legacy CPU.

2. Each piece of software (and each OS for that matter) may have different bottlenecks, depending on how it uses your hardware.

3. Premiere Pro CS5 uses CUDA only with specially designed, built-in transitions and special effects. This speeds up previewing substantially, but speeds up rendering the timeline by only a modest amount. PP CS5 does not use CUDA for rendering the timeline, but for $300+ US you can buy a CUDA-based h.264 codec plug in from the 3rd party vendor, MainConcept.

4. Vegas Pro 10 does just the opposite, but only if you render with the SONY AVC codec and you use the right settings. Previewing in Vegas derives no advantage from CUDA, unless you buy 3rd party plug ins that use CUDA for transitions and FX.

Sorry but I would have to disagree. I just did a test with Premiere Pro CS5 with AVCHD PIP (four scaled PIPs) with no effects or transistions. With GPU it took 2min10secs to render out to AVCHD, with GPU disabled it took 7min40sec. GPU loads between 60-90%. And with Vegas I get no improvement when rendering with SONY AVC codec using the right settings.