"However, we've also found that ATI cards produce better results in Blu-ray testing, with playback through the Radeon 4550 slightly smoother and providing less of a hit on other PC applications. It's also worth pointing out that ATI's technology supports full 7.1 channel HD audio through HDMI - a feature that the PNY GeForce 9400 GT doesn't offer. If you're looking for a card to build into a media PC, this may sway you towards the ATI Radeon 4550.
The nVidia PNY GeForce 9400 GT is slightly cheaper than the Radeon 4550. However, the latter offers a marginal increase on game frame rates; and more significantly, HDMI and Blu-ray support is better with ATI's 4550. Since many users will want a sub-£50 card for the video or media PC potential, this still makes the Radeon 4550 a slightly better buy over this 9400 GT, in spite of the price difference."