Another NVIDIA Ion Platform Preview
 

We tested HD and Blu-ray playback with PowerDVD running at 1920x1080 over HDMI, and we found that most content played back smoothly with between 25 and 80% CPU utilization on our simulated single-core Atom. The 1080p trailer for The Dark Knight was buttery smooth, as were high-bitrate Blu-ray titles 28 Days Later and Click. These two movies did consume more CPU cycles than the Batman trailer, but that's to be expected given the additional processing necessary to handle Blu-ray DRM, which isn't crunched by the PureVideo decode engine.

28 Days Later and Click are encoded with H.264 and MPEG2 codecs, respectively, so what about Blu-ray's third format, VC-1? We use Nature's Journey to test VC-1 performance, and on the Ion platform, playback was surprisingly choppy, pegging our single-core Atom config's CPU utilization at 100%. Nvidia says it optimized PureVideo HD for 1080p content, and that Nature's Journey playback is choppy because it's actually a 1080i movie—a format the company claims is a shrinking niche. According to Nvidia, the problem here isn't processing horsepower, but memory bandwidth. A dual-channel Ion setup, the company says, should play back Nature's Journey smoothly.

http://techreport.com/articles.x/16340