1 crossfire bridge vs 2 crossfire bridges

[demonkevy666]

my 3870s won't enable crossfire with out both on, I'm vista 64 bit.

just test out two card with out bridges on the pcb.
cards like the 4350 and 4550, that say they support crossfire should work too if that where the case.

[texasreefer]

dont get what you mean, sorry

and yes, sli works without any bridges and xfire should as well, havent tried it in a while though... they will just transfer the data via pciE then, its called software xfire/sli... it works well but usually a tad slower than propper bridge sli and xfire...

about people who needed 2 bridges... maybe you needed the second bridge?
maybe the right one has to be in place or the left one, bot not both?

Sorry, for the confusion, saaya...yeah, software enabled crossfire. HOw is that done...what software is used?

[demowhc]

Sorry, for the confusion, saaya...yeah, software enabled crossfire. HOw is that done...what software is used?

the ATi drivers take care of software CF - for low end cards there is enough bandwidth for crossfire without the need for the bridges, you can also run higher end cards but they become bandwidth restricted resulting in less performance...


edit/ I also asked ATi how many bridges to use about a year ago in a support ticket and they told me only 1 bridge is required for 4870 CF..

[texasreefer]

hmmm, yes i guess not necessary....It seems that for newer cards i.e. 4890, 5870 two connectors works best

[IronWarrior]

I have two HIS 4670 IceQ Turbo's in CFX, I use two bridges because I thought or was told by people here I think that two are better then one, has anyone really tested this out, would there be any FPS difference betweeen one or two bridges?

[MetalWaterBox]

I was wondering about one or two bridges with my 5870's through my searching on the net I found a review with two 5870's in Xfire and the reviewer said they had contacted ATI about this particular ? and that ONE bridge is all it takes and that using two wouldnt hurt but doesnt really help either...If I can find this I will post a linky.......


http://www.guru3d.com/article/radeon...-test-review/3


its under the pic with 2 bridges...lol

[villa1n]

Well I use two bridge connects on my 4870's and haven't had any problems. I use two because the directions that came with my cards said to use two. Not only did it say to use two it showed photos of the installation and it used two.

Me too, I have a Sapphire 1gb 4870 and an MSI 1gb 4870

[texasreefer]

I was wondering about one or two bridges with my 5870's through my searching on the net I found a review with two 5870's in Xfire and the reviewer said they had contacted ATI about this particular ? and that ONE bridge is all it takes and that using two wouldnt hurt but doesnt really help either...If I can find this I will post a linky.......


http://www.guru3d.com/article/radeon...-test-review/3


its under the pic with 2 bridges...lol

WOW, MetalWaterBox, awesome find....

According to the reviewers at 3dGuru...

"Though the photo shows two CrossfireX bridges only one CF strap is actually sufficient and recommended to retain better the airflow of the board. According to ATI there’s really no need for a second one unless you use 3- or 4-way CF."

Verry Interesting

[demonkevy666]

note cards in pink crossfire with out connectors, on crossfire boards.

[Nizzen]

I was wondering about one or two bridges with my 5870's through my searching on the net I found a review with two 5870's in Xfire and the reviewer said they had contacted ATI about this particular ? and that ONE bridge is all it takes and that using two wouldnt hurt but doesnt really help either...If I can find this I will post a linky.......


http://www.guru3d.com/article/radeon...-test-review/3


its under the pic with 2 bridges...lol

I have 2x Asus 5870 in crossfire. I tested 1 bridge vs 2 bridges in games and 3dmarks. Crysis, farcry 2, nfs shift, crysis Warhead, Fallout 3, 3dmark 05,06 and vantage. All tests where identical with one and two bridges. No performanceloss og gain.

But if I run my 5870 cards in x16 + x8 pci-e speed, then my average fps in Warhead goes form ~53fps --> ~42fps. Compared when I run pci-e x16 +x16 on my Evga x58 vanilla. In 3dmarks I don't loos so mutch "power" from x16/x8.

Apparently Crysis Warhead need all the bandwidt it can get

[nascasho]

I have 2x Asus 5870 in crossfire. I tested 1 bridge vs 2 bridges in games and 3dmarks. Crysis, farcry 2, nfs shift, crysis Warhead, Fallout 3, 3dmark 05,06 and vantage. All tests where identical with one and two bridges. No performanceloss og gain.

But if I run my 5870 cards in x16 + x8 pci-e speed, then my average fps in Warhead goes form ~53fps --> ~42fps. Compared when I run pci-e x16 +x16 on my Evga x58 vanilla. In 3dmarks I don't loos so mutch "power" from x16/x8.

Apparently Crysis Warhead need all the bandwidt it can get

Whoa, I guess that sounds right and odd. My board and cards are 16x and 8x but my score are similar with others to a certain extent with Vantage and Crysis... But it runs like garbage. You think that's the cause? What did you do to get different pcie freq? I was debating if my board is the cause of retardness... Crysis, even though it say 40 it'll look like 20

[Theorw]

I think when i had my 4850 1gig with 2 bridges i d get 1-2 more frames in crysis but then again i am not sure...But chances are that its true...

[Nizzen]

Whoa, I guess that sounds right and odd. My board and cards are 16x and 8x but my score are similar with others to a certain extent with Vantage and Crysis... But it runs like garbage. You think that's the cause? What did you do to get different pcie freq? I was debating if my board is the cause of retardness... Crysis, even though it say 40 it'll look like 20

When I have a pci-e card in the third pci-e x16 slot, the pci-e config on the three pci-e slots is: x16-x8-x8. When only the first two pci-e slots used, the config is x16-x16-x8.

The third pci-e slot runs only in pci-e x8 on Evga x58 vanilla. Only MB with nf 200(s) have 3 pci-e x16 electrical or more

[nascasho]

Thing is that the LE is locked at 16x/8x/4x/8x and I get some bad results and get benches on par with others, but the benches are too small to compare spec to spec.

Crysis in general anyways. In some areas it'll lag... really bad. I get microstutter pretty bad too. Game says 40+ fps and it'll look and feel like 20. I also don't hear too many complaints about CFX performance for some reason either, yet my benches are on par... and it sucks.

I dunno if it was because of the 16x and 8x setup or not even the though the bottleneck isn't THAT bad.

P24965

[SocketMan]

"Dual channel interconnect" is the term (describing the crossfireX bridges) I've heard somewhere.


When in doubt - use 3+ cards and 4 sticks of ram
http://picasaweb.google.ca/lh/photo/...eat=directlink

[texasreefer]

Maybe you heard that here http://ati.amd.com/products/radeonhd3800/specs.html

Located under the Crossfire config of the 3800s. NOtsure what that means "Dual channel interconnect is not required for ATI CrossFire, and may not be included in all product configuration."

[SocketMan]

Yea they even call it "high performance",nice find

I am guessing that maybe in the future there will be a need
for using 2 per 2 cards,probably when a lot of data transfer
is taking place (high resolutions+IQ+6+monitors).

[darckhart]

sorry to drag up this old topic, but this is my first xfire setup (2x5850), and i was wondering the same thing. i've tried 1 and 2 bridges and the only game where it seems to make a difference is in crysis. BUT 2 bridges somehow makes it worse! the stuttering is more pronounced in certain areas AND sometimes the framerates will drop down to <10 for no apparent reason. removed 1 bridge and played the same part and it's ok. repeatable about 4 times. soo my question, has there been any real consensus? or is it just a per game thing still for now? the other two games i'm playing now (mw2, fc2) i notice absolutely no change between 1 and 2 bridges.

[Particle]

Just use one bridge. That's the way I think most of us do it, and there's no benefit to using two. It only seems to cause problems.

[WrigleyVillain]

Heh not railing again you darck it's just this is one of those topics, like whether or not it's a good idea to disable the page file when you have a lot of RAM, about which there is really never consensus and that seems to be a constant source of confusion and questions.

[texasreefer]

oh well....deal with it! If it bothers you so much then don't respond to something that may concern someone else. Stick that in your 280 and smoke it, deadhead. This post has nothing to do with your old arss ancient setup.

[WrigleyVillain]

oh well....deal with it! If it bothers you so much then don't respond to something that may concern someone else. Stick that in your 280 and smoke it, deadhead. This post has nothing to do with your old arss ancient setup.

LMAO! And that from someone named texasreefer. ANYWAY, my post wasn't even a complaint really so chill the f out. Just about the fact that this seemingly simple question is never resolved and it's kind of hilarious.

BTW I got this 280 as a straight trade for a 4870 until the 5800 series comes down to earth. Not a bad deal, even a rabid ATI fanboy should be be able to admit.

[texasreefer]

Good trade...

[WrigleyVillain]

Thanks. I have ran ATI cards only since X800 and wanted to try Nvidia drivers for a change for IQ comparisons and different AA modes. I kind of hate Nvidia but I'm really glad I did this, there is a definite nice difference in some games.

Actually originally traded for a 260 but it blew up (literally) after a week and MSI sent this nice reference 280 so I got pretty lucky.

[Hell Hound]

@ Higher res you will notice micro stutter with just one cable,@ least on my 3870 gddr4's.