NVIDIA's PureVideo HD: HD-DVD Playback on the PC
by Derek Wilson on July 22, 2006 10:00 AM EST- Posted in
- GPUs
The System, Tests and Performance
The system NVIDIA brought with them was a Shuttle SD31P featuring an Intel Pentium D 830 and a Toshiba TS-L802A HD-DVD player. While this is on the low end of what we would want to use in a multimedia box, specs like this could fit in with people who want a quiet, lower power media center box for their living room. Many of the early adopters of HD-DVD and Blu-Ray on the PC will likely be enthusiasts with high quality components who won't run into usability issues with new media, but those who want to spend as little as possible may have a more difficult time getting their HD-DVD or Blu-Ray to work as expected. Even those who wish to run a completely silent rig may find a lack of quality without offloading some of the processing to a graphics card.
Full specs of the system NVIDIA brought for us to test are as follows:
In order to fully test the playback capabilities of the system, we tested the Japanese version of The Chronicles of Riddick, which uses H.264 encoding. This is by far the most strenuous video test available right now.
Sample Riddick videos
Watching the videos will give you an idea of what the highest bit-rate Japanese titles will be like without a high speed CPU or good video decode acceleration on the GPU. Keep in mind that the framerate mismatch between the output of the TV and the DV cam, the scaling, and the compression all decrease the impact that dropped frames have. Recording a video of a display using a DV cam is always going to result in reduced quality, so subjectively you'll just have to trust us when we say that the GPU accelerated playback was smooth and didn't show dropped frames. The difference are much more noticeable in person and we can say without reservation that the Japanese version of Riddick is unwatchable on a Pentium D 830 without PureVideo HD at this point.
As PureVideo HD performance is dependant on the GPU's core clock speed, the impact of PureVideo will vary depending on the speed rather than the 3D power of your graphics card. For example, our MSI 7600 GT HDCP runs at a default 580 MHz core speed. This makes it a more effective PureVideo card than a 7900 GT running between 450 and 500 MHz. NVIDIA allowed us to underclock the MSI graphics card and test a variety of settings between 350 MHz and 580 MHz in order to fully understand the way performance varies versus GPU clock speed.
To test the performance of PureVideo HD, we ran perfmon while playing back Riddick at different GPU clock speeds. Riddick was playable down to 450MHz, and PureVideo HD did have some impact on performance even as low as 400MHz. There wasn't any perceivable quality difference between running the GPU at 350MHz and running without GPU acceleration.
Without PureVideo HD running The Chronicles of Riddick (Japan), the CPU was at 100% the entire time. Enabling PureVideo HD with the GPU running at retail speed (580MHz), CPU usage dropped to about 80% on average. With other titles using VC-1 content, we saw CPU usage at around 80% without GPU assistance. Turning on PureVideo HD gave us about 60% CPU usage. In general, it looks like a 580 MHz NVIDIA GPU is capable of decreasing the load on a Pentium D 830 by about 20% in any given situation. This isn't a huge drop, but it is definitely significant and can help in those tough situations (like H.264 encoded imports).
We did scan through a number of features like scene selection, bookmarks, and picture in picture (viewing multiple tracks at once). All of these features run as they would on a CE player, though interface consistency can be a problem (some require keyboard or mouse only for different menus or features).
Our final test takes a look at system level power draw with and without PureVideo HD enabled. We ran our system through a Kill-A-Watt device and looked for maximum power draw over a specific clip of the movie. While our Kill-A-Watt doesn't record average power, we eyeballed the range of and frequency of power levels and came up with a very rough average. We did this for both The Chronicles of Riddick (Japan) and Swordfish. Power draw is in Watts and listed avg/peak. Idle power is 127W.
It is pretty clear that there isn't a real power advantage with PureVideo HD at this point in time. As more of the pipeline is moved onto the GPU, the specialized hardware could potentially increase the efficiency of the process. This could lead to lower power draw, but at this point in time, all we are doing is shifting where the power is going.
We won't be able to get our hands on another drive for a while, so although we have ATI cards that feature HDCP, we are unable to compare AVIVO to PureVideo HD at this time. Certainly we are hoping to see a similar level of quality from ATI. Our comparison will be available as soon as we are able to get hardware and drivers.
The system NVIDIA brought with them was a Shuttle SD31P featuring an Intel Pentium D 830 and a Toshiba TS-L802A HD-DVD player. While this is on the low end of what we would want to use in a multimedia box, specs like this could fit in with people who want a quiet, lower power media center box for their living room. Many of the early adopters of HD-DVD and Blu-Ray on the PC will likely be enthusiasts with high quality components who won't run into usability issues with new media, but those who want to spend as little as possible may have a more difficult time getting their HD-DVD or Blu-Ray to work as expected. Even those who wish to run a completely silent rig may find a lack of quality without offloading some of the processing to a graphics card.
Full specs of the system NVIDIA brought for us to test are as follows:
CPU: Intel Pentium D 830
RAM: 1GB DDR2 533
Chipset: Intel 945G
Graphics: MSI 7600GT w/ HDCP
Display: Westinghouse LVM-42W2
HD-DVD Drive: Toshiba TS-L802
OS: Windows XP SP2
HD-DVD Player: CyberLink PowerDVD (for HD-DVD)
In order to fully test the playback capabilities of the system, we tested the Japanese version of The Chronicles of Riddick, which uses H.264 encoding. This is by far the most strenuous video test available right now.
Sample Riddick videos
Watching the videos will give you an idea of what the highest bit-rate Japanese titles will be like without a high speed CPU or good video decode acceleration on the GPU. Keep in mind that the framerate mismatch between the output of the TV and the DV cam, the scaling, and the compression all decrease the impact that dropped frames have. Recording a video of a display using a DV cam is always going to result in reduced quality, so subjectively you'll just have to trust us when we say that the GPU accelerated playback was smooth and didn't show dropped frames. The difference are much more noticeable in person and we can say without reservation that the Japanese version of Riddick is unwatchable on a Pentium D 830 without PureVideo HD at this point.
As PureVideo HD performance is dependant on the GPU's core clock speed, the impact of PureVideo will vary depending on the speed rather than the 3D power of your graphics card. For example, our MSI 7600 GT HDCP runs at a default 580 MHz core speed. This makes it a more effective PureVideo card than a 7900 GT running between 450 and 500 MHz. NVIDIA allowed us to underclock the MSI graphics card and test a variety of settings between 350 MHz and 580 MHz in order to fully understand the way performance varies versus GPU clock speed.
To test the performance of PureVideo HD, we ran perfmon while playing back Riddick at different GPU clock speeds. Riddick was playable down to 450MHz, and PureVideo HD did have some impact on performance even as low as 400MHz. There wasn't any perceivable quality difference between running the GPU at 350MHz and running without GPU acceleration.
Without PureVideo HD running The Chronicles of Riddick (Japan), the CPU was at 100% the entire time. Enabling PureVideo HD with the GPU running at retail speed (580MHz), CPU usage dropped to about 80% on average. With other titles using VC-1 content, we saw CPU usage at around 80% without GPU assistance. Turning on PureVideo HD gave us about 60% CPU usage. In general, it looks like a 580 MHz NVIDIA GPU is capable of decreasing the load on a Pentium D 830 by about 20% in any given situation. This isn't a huge drop, but it is definitely significant and can help in those tough situations (like H.264 encoded imports).
We did scan through a number of features like scene selection, bookmarks, and picture in picture (viewing multiple tracks at once). All of these features run as they would on a CE player, though interface consistency can be a problem (some require keyboard or mouse only for different menus or features).
Our final test takes a look at system level power draw with and without PureVideo HD enabled. We ran our system through a Kill-A-Watt device and looked for maximum power draw over a specific clip of the movie. While our Kill-A-Watt doesn't record average power, we eyeballed the range of and frequency of power levels and came up with a very rough average. We did this for both The Chronicles of Riddick (Japan) and Swordfish. Power draw is in Watts and listed avg/peak. Idle power is 127W.
| System Power Draw | ||
| Riddick | Swordfish | |
| CPU Only: | 185/193 | 179/185 |
| PureVideo HD: | 185/192 | 175/180 |
It is pretty clear that there isn't a real power advantage with PureVideo HD at this point in time. As more of the pipeline is moved onto the GPU, the specialized hardware could potentially increase the efficiency of the process. This could lead to lower power draw, but at this point in time, all we are doing is shifting where the power is going.
We won't be able to get our hands on another drive for a while, so although we have ATI cards that feature HDCP, we are unable to compare AVIVO to PureVideo HD at this time. Certainly we are hoping to see a similar level of quality from ATI. Our comparison will be available as soon as we are able to get hardware and drivers.
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yzkbug - Saturday, July 22, 2006 - link
I have a $5K question (the cost of a new TV) unanswered by this article. Do you absolutely need an HDCP-enabled TV to watch HD movies on PC? The slide on page 2 shows that a monitor can be connected either via Analog (VGA or Component) or via Digital (DVI or HDMI with HDCP). So, does it mean that it is possible to watch HD over Analog without any PQ degradation? Also, does it mean that DVI without HDCP is a no-go?Bowsky - Saturday, July 22, 2006 - link
HDCP is only required to view HD content is an Image Contrait Tokien (ICT, I think thats its name) is present on the disc. If it's not there the media can be played at full resolution over any connect such as nonHDCP-DVI, VGA, component, etc.To answer your $5,000 question, the movie companies have decided to wait until 2010 before using the ICT on any media. After that all media will be down-scaled if played over non-HDCP connections. So my answer to you is buy the HDCP television set. It won't be required immediately, but will unfortunately be required in the near future.
Also, most new HDTVs on sale these days have HDCP so ther shouldn't be too much to worry about when buying.
DerekWilson - Sunday, July 23, 2006 - link
Our understanding of the situation is that any DIGITAL playback requires HDCP or no image will be displayed (under current PC video player technology -- downscaling may be possible in the future).Currently all titles will be able to play full resolution Analog (component, vga), but in the future this will not be allowed either.
non-HDCP DVI and non-HDCP HDMI will never playback full resolution HD content distributed on HD media with HDCP protection enabled. This is essentially all titles.
If you want digital playback of HDs or BDs, you can't do it without an HDCP television. If you don't mind analog playback, your fine for the next few years.
Renoir - Sunday, July 23, 2006 - link
Just so I understand you Derek are you saying that full resolution playback over a digital connection will not be allowed regardless of whether the image constraint token is used or not and that full res will only be allowed over analogue until the ICT is used? If so that sucks big time. Would then have to hook up my monitor via both vga and dvi depending on if I'm watching a hd disc or not (assuming of course I still have my current monitor by the time I watch hd discs off course).DerekWilson - Sunday, July 23, 2006 - link
this is the way I understand it.Renoir - Monday, July 24, 2006 - link
Bummer! Was hoping the lack of the ICT would allow me to use dvi at full res. I imagine it's because they're more worried about people getting a perfect digital copy rather than capturing the analogue at full res and then converting it to digital. However I'm not aware of any dvi capturing devices although there are plenty of component ones. Does anyone know of any hi res digital capturing devices as I'm curious now :-)DerekWilson - Monday, July 24, 2006 - link
we wanted to build one to analyse video output of graphics cards without relying on screen capture utilities ... it shouldn't really be that difficult.Renoir - Monday, July 24, 2006 - link
cool! Perhaps in terms of piracy they feel that it's less neccesary to protect the full res analogue video than a bit for bit accurate dvi feed. If so then they must be thinking that people would find pirated videos that were redigitised from component etc (albeit at full res) less compelling than one straight from dvi. What other reason/s do they have for allowing full res over analogue but not over digital?Renoir - Monday, July 24, 2006 - link
Just realised I haven't taken any analogue copy protection such as macrovision into account. Any info on this aspect? If it's present then that would pretty much answer my last question.vhx500 - Saturday, July 22, 2006 - link
On page 2, you mention plaing Riddick and Swordfish, but you are displaying a screenshot from The Bourne Supremacy?