How does Crossfire work?

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ruvolk

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I mean I know how it works, but which card do I connect to the monitor?
I'm planing of using two ATI 5770's together.
I already have one 5770 running and connected to the monitor via HDMI.
Would I just buy another and put the CrossFire Bridge on the cards and have one HDMI coming from one GPU connected to the monitor.
Sorry I'm confused.
I'm also planning of using the ASUS Sabertooth X58.
 
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Both that and the one JDfan suggested will work. The brand does not matter. They are all built to the same specification.

The standard length of approximately 2 3/8" (61mm) on connection center for a crossfire interconnect cable (CIC) easily accommodates the connection from PCIEX16_1 to PCIEX16_2. This standard size CIC is what was included with each 5850 I've purchased. One of the same size also came with my motherboard.

If you're going to add a 3rd card at some point - even though it doesn't seem like it - the standard length CIC will reach...
In crossfire there is a dominant card, and secondary cards, the one you currently have your monitor attached to would likely remain as your dominant card, the second card will do work, ship the data back to that card, and then it will feed it out to the monitor so the cables into the back of your PC remain exactly the same.
 

You have the right idea.

You can leave your monitor attached to the card you already have in. Unplug your PC to start. Install the new graphics card in the PCIEX16_2 port next to your other card. Use the Crossfire Interconnect Cable to bridge the cards. Connect the card to your power supply with a 6-pin connector (usually has a PCI-e stamp on it), plug in the PC and boot up.

If things don't look quite right (you can't enable crossfire or you don't see two cards under graphics hardware in catalyst - Primary and Linked Adapters), you'll most likely have to uninstall and re-install your Catalyst Control Center and drivers.

To uninstall/re-install:

1) Go to control panel->add/remove programs or control panel->programs->uninstall a program (depending on your OS)
2) Double-click ATI Catalyst Install Manager and choose the 'Express Uninstall' option
3) Restart
4) Run Driver Sweeper (free download from phyxion.com), check the ATI Drivers only and click 'Clean'
5) Restart
6) Install the ATI drivers/Catalyst software

Each time I've added a graphics card to my system, I've had to re-install the drivers.
 

ruvolk

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Sorry, I just have one more question.
Were would I get crossfire bridge from?
The motherborad?
Because I heard the ASUS Sabertooth X58 comes only with a SLI bridge.
 
Most ATI video cards with crossfire capability come with one. Check the 'what's in the box' part of the description on your favorite PC parts dealer's web site. If you live near a microcenter, they'll let you check in the box to see if it's there. If it's not, you can get one for $10-$12 in-store. Newegg has them for $10.99, but they're currently charging $5.99 to ship.
 

Both that and the one JDfan suggested will work. The brand does not matter. They are all built to the same specification.

The standard length of approximately 2 3/8" (61mm) on connection center for a crossfire interconnect cable (CIC) easily accommodates the connection from PCIEX16_1 to PCIEX16_2. This standard size CIC is what was included with each 5850 I've purchased. One of the same size also came with my motherboard.

If you're going to add a 3rd card at some point - even though it doesn't seem like it - the standard length CIC will reach from the 2nd to the 3rd video card slot. It did on my motherboard. Just from looking at your motherboard, all the PCI-express slots you'd be using won't require a CIC longer than standard length. All of the slots on your motherboard you'd use for video cards are of equal distance to one another.
 
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