Which graphics card is better? ATI Radeon HD 5450 1gb vs NVIDIA GeForce 8400GS 1gb?

http://www.ebay.co.uk/itm/VTX3D-ATI-Radeon-HD-5450-1GB-Graphics-Video-Card-/180878032721?pt=UK_Computing_Computer_Components_Graphics_Video_TV_Cards_TW&hash=item2a1d2bbf51#ht_1300wt_1344

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