I'm using ati radeon hd 3870x2 on the computer, but I have a sapphire hd 3850, and I want to do a crossfire whit this 2 ghafic carts, I have a power surce whit 1Kw, a motherboard asus workstation p5k64 WS that suport 4 graphic carts. 

The question that I have, is abaut the conexion betewn the 2 graphic carts, the sapphire hd 3850 dosen't have any tipe of conexion for using the internal crosfiree conexion (this http://www.svideo.com/cr.html), so if I buy a external crosfire conexion, I will be able to do crosfire? and where I buy a external crossfire conexion.

thx for the help

All of Sapphire's HD3850 PCI_e cards have one or two XFire Bridge connectors on them .. you ain't looking in the right place if you can't see it !

.. and it's the exact same for their Ultimate and Zalman Cooler versions too. If the card you have has no XFire bridge connectors, then it's an AGP card.

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