HD Video Playback: H.264 Blu-ray on the PC

The Test

As we previously indicated, we need to use at least a Core 2 Duo E6400 in order to avoid dropping frames while testing graphics card decode acceleration under X-Men: The Last Stand. As we also wanted an accurate picture of how much GPU decode acceleration really helps, we needed to use a CPU powerful enough to avoid dropping frames even under the most stressful load without GPU assistance. Thus we chose the Core 2 Duo X6800 for our tests. Using this processor, we can more accurately see how each graphics card compares to the others and how much each graphics card is able to assist the CPU.

We tested CPU utilization by using perfmon to record data while we viewed a section of X-Men: The Last Stand. The bookmark feature really helped out, allowing us to easily jump to the specific scene we wanted to test in Chapter 18. In this scene, the Golden Gate is being torn apart and people are running everywhere. This is one of the most stressful scenes in the movie, reaching a bitrate of over 41 Mbps at one point.

Unfortunately, we haven't found a feature in PowerDVD or another utility that will allow us to count dropped frames. This means we can't really compare what happens to the video quality when the CPU is running at 100%. In lieu of dropped frames, we will need to stick with CPU overhead as our performance metric.

For reference we recorded average and maximum CPU overhead while playing back our benchmark clip with no GPU acceleration enabled.

Here is the rest of our test system:

Performance Test Configuration
CPU:	Intel Core 2 Duo X6800
Motherboard(s):	ASUS P5B Deluxe
Chipset(s):	Intel P965
Chipset Drivers:	Intel 7.2.2.1007 (Intel)
Hard Disk:	Seagate 7200.7 160GB SATA
Memory:	Corsair XMS2 DDR2-800 4-4-4-12 (1GB x 2)
Video Cards:	Various
Video Drivers:	ATI Catalyst 6.11 NVIDIA ForceWare 93.71 NVIDIA ForceWare 97.02
Desktop Resolution:	1920x1080 - 32-bit @ 60Hz
OS:	Windows XP Professional SP2