I currently have a XFX ATI Radeon HD 4870 in my computer with 512 dedicated graphics, I want to buy another graphics card to insert in my system and I have been looking at this one:
http://www.svp.co.uk/technology/components/graphics-and-video/ati-radeon-4000-series/radeon-hd-4890/xfx-ati-radeon-hd4870-1024mb-pci-express-20-hdtvdvi-d-graphics-card-xfx-01005_xfx-01005.html
Will this work fine with my card even though it has more dedicated memory? Will Crossfire X be enabled with both of these cards in my system?

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