CPU at 16%?

[Nicholas de Kock]

Any ideas why Vegas is only using 5 of my 8 cores at 16% on my new i7 2600 CPU with 16Gb of Ram? A 30 second clip with Magic Bullet Looks takes over 16 minutes to render! Adobe Media Encoder gives me full 100% CPU usage. What's wrong here? My 4 year old Q6600 CPU was faster.

[Jeff Harper]

If not for the Adobe thing you mention, I would guess that you might need to reseat your heatsink, or at least make sure all four pins are in all of the way.

Improper application of thermal paste, etc will cause this kind of issue you describe. Not saying this is what you issue is, but it fit the bill of what you describe.

[Nicholas de Kock]

Jeff I don't understand this either, completely whack. Here is a screenshot of a Vegas render compared to an Adobe Media Encoder transcode. Fan is secured properly, temperatures running at 41'C.

[Jeff Harper]

Nick, install and run CoreTemp and do a render, and see how your temps run on all your cores. If they are uneven by much then you might need to reinstall your heatsink. This will at least give you more info to work with. I only recommend this because it happened to me. My renders were fine, but my core temps varied a lot from core to core, and I could figure out what was up.

It so happened I bought a new cooler for my CPU, and when I removed the old one I found I hadn't fully inserted one of the heatsink pins properly previously, and my thermal past was very unevenly spread to boot. I have installed heatsinks, CPUs a number of times, but really screwed it up that time, apparently.

When installed my new heatsink/cooler, the temps were much more even across all 6 cores. Not very scientific, but if this can help, you might try it.

[Nicholas de Kock]

Thanks Jeff, downloaded and tested, core temperatures are roughly even across the board. The latest update of Vegas isn't very stable either, I experience a lot of crashes.

[Jeff Harper]

If you haven't already done so, you might need to reinstall windows. I had to. I find the latest version to be 'mostly' fine. I had some intermittent crashes that have stopped, and I find panning a scanning things to be trouble some, but otherwise it has been ok.

Ideally you don't want 100% utilization of your CPU, there should be some headroom left while rendering. 100% means your CPU is completely taken and leaves no room to operate other programs.

I find oveclocking will snap the cpu usage into a higher range, even at lower overclocks. Mine was at 25% or so, but when I overclocked it shot up to 80-90%, and now when I on rare occasion revert to stock settings, it's still very high. Very weird, I have no idea how this stuff works. It's like the overclock somehow opens up things, even after you go back to the default settings.

[Gerald Webb]

Whats your Dynamic Ram set to in Vegas?
I had this last week, had Ram set to 5GB for doing some long previews and forgot to change it back down, was rendering at 20ish %.
Changed it back down to 500Mb and started again and it shot up to 68% CPU usage.

[Mark F. Allen]

The image of your TaskManager means you may be running single-threaded code. 12% means one thread on a four core hyperthreading CPU. The threads jump around from core to core. They don't just sit in one core. The image below is my CPU running a single-threaded instance of Prime95. Other things going on in your computer can add a few extra percent beyond the main thread. It could also be multi-threaded if the chokepoint is somewhere else than the CPU.

If your rendering is slower it could be because it's using the GPU for rendering and it's slower than your CPU. Vegas 11 made substantial changes to the amount of GPU support. You can tell for sure by getting a GPU monitor utility. Just google for "GPU monitor". There's tons of them. So if your GPU's getting hit hard and your CPU isn't then tell Vegas to use the CPU instead. I'm not sure how. I'm running Vegas 10. There's also an option in older versions of Vegas which allows you to limit the number of threads. But I don't see how that would change without you doing it manually.

[Nicholas de Kock]

Mark you where right about the GPU doing the work, I disabled the GPU in the preferences of Magic Bullet Looks & I now have full CPU utilization....but....

I then did a render with the GPU enabled/disabled & the GPU kicks the CPU's ass even though it's an Intel 3.40Ghz i7, the GPU rendered in half the time. This makes me wonder, if I put two graphics cards in SLI will this improve render times? It appears that the CPU isn't that important after all when using Magic Bullet Looks, spending some money on a proper high end graphics card might speed up my workflow.

[Mark F. Allen]

Originally Posted by Nicholas de Kock

This makes me wonder, if I put two graphics cards in SLI will this improve render times?

I'd ask Red Giant. I've seen people asking about GPU acceleration in Vegas with multiple video cards and haven't yet seen a definitive answer. And it may be specific to the plugin. It's mostly gamers who have SLI rigs so I guess there's not that many people around who can test it.

With all the GPU acceleration being added lately there's definitely an advantage to a high-end video card. But it seems awfully specific to exactly what you're accelerating. Some things are faster on the GPU and others are faster on the CPU even with a fast video card. Personally, I've always gotten one faster video card rather than two slower ones. There's just too many situations where two in parallel are not used very effectively if at all.

[Ian Stark]

I'm just reporting this as something I have read in several places but it's not from personal experience or knowledge: Vegas only supports one GPU at this time.

[Jeff Harper]

This is a great thread. I turned off GPU and am finding much faster rendering without in my case. A render that took 1 hour & 22 minutes with GPU on, is now taking 1 hour.

I think for a bluray project that that is pretty fast. The 720 60p project is 2 1/2 hours long with color correction so I think that 1 hour is reasonable.

[Nicholas de Kock]

Jeff this definitely brings a lot of variables to question. What graphics card do you have? I'm running the ATI 6870 with 1Gb of RAM at the moment. Magic Bullet Looks with GPU rendering makes a massive difference compared to CPU. I'm not sure why at first my renders where ultra slow but after disabling & enabling GPU it seems to have returned to normal. There will probably be situations that favour CPU over GPU.

[Jeff Harper]

I'm running a GTX 460 SE which is not so hot, apparently!

[Ron Windeyer]

Originally Posted by Jeff Harper

This is a great thread. I turned off GPU and am finding much faster rendering without in my case. A render that took 1 hour & 22 minutes with GPU on, is now taking 1 hour.

I can endorse Jeff's comment. I have a HP laptop, (I7 @ 2Gh) the video card is a 1 Gb Radeon something, with up to 5 Gb of shared video. Works fairly well for gaming. However for video I create Sony AVC mp4 files, 1920x1080, 50P. Pretty heavy work. A 2.25 clip took 7.03 to render using CPU only, and 11.30 with GPU enabled.

As a side note, I'm getting a pretty even spread of activity on the task monitor, and CPU usage runs from 55-60%.