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Vegas Pro 11 listing my CPU (not GPU) under GPU acceleration pull down
I have an ATI Firepro 7750 video card with the latest (two days ago) video drivers. Up until the installation of these video drivers, the GPU acceleration pull down just listed “off”. Now it lists “off” and “AMD quad core Opteron…..”, which is the CPU, not the GPU. Rendering with this option takes longer and is more CPU intentsive (75% CPU loaded) versus the “off” setting (25% CPU loaded). Anyone else seen anything like this?
I am not sure that Sony is guilty for not listing my video card, as the AMD/ATI web site indicates that the OpenCL drivers for the 7750 are “beta”, so VP11 may not be able to recognize the card just yet. But I have no idea why it is listing my CPU (an AMD quad core Opteron).
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3 Replies
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Yeah sometimes being on the bleeding edge hurts…
Lance Bachelder
Writer, Editor, Director
Irvine, California -
AMD has a native CPU implementation of OpenCL for the x86… that’s certainly what you’re seeing there. It’s useful for OpenCL software that wouldn’t run otherwise.
On the other hand, if you’re seeing longer rendering times with the enabled, but only see 25% CPU load when it’s disabled, you have problems beyond OpenCL. You should see something in excess of 90% CPU load when rendering, unless you have explicitly told Vegas not to use all CPU cores.
All rendering will find a bottleneck — the weakest link in your rendering chain. The CPU should be your system’s bottleneck. When you line up everything else that’s reasonable to have in a modern PC, the CPU is the one that’s going to be too slow. Watch out for single-threaded plugins, or a single drive being used for all rendering (you want the drive to operate at streaming speeds, but with too much media, it tends to do lots of seeking — seeks on HDDs are 100x slower than streaming).
-Dave
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Thanks for your response. To clarify, my PC is a custom server motherboard with two quad core Opterons, 8 G ram, Win7x64 on one drive, and separate “media” striped dual RAID drives. Somewhat bleeding edge when built 4 years ago, but still no slouch in 2012.
When rendering standard def video (old video tapes to MPEG-2 for DVD Arch) in VP09 xs64, all 8 cores load up equally at an average 75%, and a 1:20 minute video renders in 40 seconds. Repeating the same render effort with VP11 x64 (no GPU acceleration) loads all 8 cores to an average 25-30%, with 4x render times. Same settings, same OS, same motherboard, same CPUs, same GPU. Now admittedly there may be some random setting difference between version 9 and version 11, but a four fold increase in render times?
Regarding OpenCL, poking around on the ATI web site revealed a web page that seemed to indicate that the first generation FirePro cards (like mine) are not yet fully OpenCL 1.1 compliant, but are only OpenCL 1.0 compliant (https://developer.amd.com/sdks/AMDAPPSDK/pages/DriverCompatibility.aspx); the 7750 is clearly listed as “beta”. Now the page may be out of date, and the difference between versions 1.0 and 1.1 may not be significant, but I am noting that it may not be Sony’s fault that the card does not show up under GPU acceleration, but rather ATI has not updated its drivers for its older video cards yet.
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