Gigabyte says no crossfire bridge needed!!!

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dhoke

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Hi Folks--I'm just about to purchase my motherboard and I'm attempting to crossfire 2 Gigabyte 4890 OC cards with factory installed Zalman coolers. No-one agrees on on the number of crossfire bridges needed and now Gigabyte says I don't need one at all???

Question:
"I purchased two of these cards for crossfire and now I am wondering if I can even use these in crossfire. If both crossfire bridges are needed then these cards are not crossfire-capable because one of the crossfire connection points is blocked by the aftermarket Zalman cooler! The Manual says to connect both crossfire bridges in the section on setting up the hardware although in the beginning of the manual it says 1 or 2 crossfire bridges needed in the section on crossfire hardware requirements. Please help--Thanks"

Response:
"No bridge should be needed, the ati software should allow for crossfire to be enable if you are using an Crossfire supported motherboard."

Are they Kidding??? I haven't purchased a motherboard, however, if Gigabyte is incorrect, I now know that I need extra long flexable crossfire bridges to clear the cooler on the top card. I know need a board with no more than two slots between the x16 slots so a 100 mm bridge (87 mm between connectors) can have enough slack to clear the cooler on the top card. There are 20 mm between slots on center. Asus Crosshair and Gigabyte boards have two slots between the x16 slots but the MSI board has three. (I'm going with an AM3, 790FX board)

Now I'm more confused than ever!
 

paperfox

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Woh I dont know what that Gigabyte guy was smoking, but from what I know about crossfire is that the bridge is required for most cards. There are a few exeptions:
http://ati.amd.com/technology/crossfire/charts.html
The lighter peach color dose not require a crossfire bridge.

You should only need ONE crossfire bridge for all crossfire (not 100% but i havent heard otherwise). Some people choose to put both believing in the theory that it increases the bandwith between the cards and thus improving performance.

If you can id get a motherboard with two slots between the pcie slots, this will help improve cooling of the cards.
 
Technically those cards can run in crossfire without a bridge, but only certain drivers allow it and it causes a performance loss. Anyway, yeah, get some long crossfire cables. You only need one crossfire bridge. The second is to allow you to add a third or fourth card, but when you only have two cards you only need one cable.
 

dhoke

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My Thanks to all for your responses.

I did write an earlier post questioning the number of crossfire bridges needed and again got varied responses.

This should not be that confusing--I hope that someday someone at Toms writes a definitive article on this topic. Gigabyte's response was less than informative.

I agree with megamanx00 that only one bridge should be needed. Otherwise you could never crossfire more than two cards (not that anyone should). If only one bridge is needed then I can use the 70 mm bridge (63 mm on center) to connect the cards because only one of the two crossfire connectors on the card is blocked.

Now I just need a motherboard to add to this system (in boxes):

965 (125 watt)
8 gig ocz platinum amd edition Cl-7 1.65volt
(2) Gigabyte 4890 OC crossfired
300gb Velociraptor
Corsair 850tx
Antec 900

I like the Asus Crosshair, Gigabyte ud5p, and the MSI gd70.

The Ram is my biggest concern--I got a good deal on this hard-to-find ram.

Any input in this will be appreciated
 
Only 1 is needed, but 2 gives benefit if you need to send more, but the benefit approaches nil because the need is limited in rare situations.

Think about multiple cards even then you would be able to do 2 per card they just have longer final loop closure.

A-B-C-D and then ALL the way back from D-A.

1 should be enough for just 2 cards, I'd only worry about it for more than that.

 

$500PCenthusiast

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:bounce: man! ty!
Just bought a second Sapphire HD 5570. Thought I remembered reading that a bridge would not be required, but the one already installed has the connector on the vc. Started getting worried when looking for quick info netted nothing saying no bridge was required. A wiki page said only older dual card solutions used a software connect to avoid y-dongle needs. It was easy to navigate to the .jpg from AMD showing this card needed no bridge when paired with another. The relief I was looking for. Btw, it is a 2GB vc, which made me nervous about how the card would handle that much RAM. The card is super stable & low heat even w/ the cheap stock cooler. Pretty excited about hookin up this budget rig w/ dual GPUs & 4GB dedicated video RAM!! Amazing what $600 can buy in tech these days. (890nb/850sb, Phen IIx4 965, 8GB Plat. Corsair DDR3).
 
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