nVIDIA has announced PureVideo HD technology in order to accelerate high definition video playback on conventional PC computers. According to their website PureVideo delivers high quality HD video for Blu-ray and HD-DVD formats with reduced CPU load and power consumption with support up to 1080p resolution.

Available on HD DVDs and Blu-ray discs, high-definition movies are bringing an exciting new video experience to PC users. NVIDIA® PureVideo™ HD technology lets you enjoy cinematic-quality HD DVD and Blu-ray movies with low CPU utilization and power consumption, allowing higher quality movie playback and picture clarity.
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The PureVideo HD processing core offloads the CPU and 3D engine of complex video tasks, allowing for higher quality movie playback and picture clarity. PureVideo HD technology delivers ultra-smooth, high-definition H.264, VC-1, and MPEG-2 movie playback with low CPU utilization and power consumption.

Source: nVIDIA