4 6770s in crossfire

[fultzy92]

simple question: i would like to know how exactly 4 6770 (sapphire) will stack vs. just 1. can any one help me?

 

[leenoshiro]

iirc, 6770 don't support quad crossfire and crossfire 6770 would suffer from microstutter. You're better off with a single 6950.

 

[amuffin]

Not possible. You can't quad crossfire 6770's.

 

[megamanx00]

Not possible. You can't quad crossfire 6770's.

Yes you can. The only requirement is that at least 2 of the cards have two crossfire connectors like this one

http://www.newegg.com/Product/Product.aspx?Item=N82E16814150540

 

[megamanx00]

Well this cheaper power color also has 2 crossfire fingers

http://www.newegg.com/Product/Product.aspx?Item=N82E16814131434

Anyway, you will notice that many of the non reference cards only have one crossfire finger. If you had two such cards as card 1 and card 2 while having the cards with dual connectors as card 2 and 3 you could connect them all with 3 CF bridges. Spacing may also be an issue as most of the cards with two CF fingers are two slot designs.

 

[monsta]

Quad 6770 isnt worth it in my opinion even if it does work.....
You are better off with a single card solution like a 7970 that has the guts and vram for the latest games without the hassle and the heat from 4 cards.

 

[de5_Roy]

you might be able to quad-fire 6770 (total peak gfx card power consumption would be nearly 400w while a 7970 uses roughly 250-260w at stock settings), but it'll be better in the long run to buy 2x $200 gfx cards and cfx/sli them or buy a single $300 gfx card and skip all the hassles with cfx/sli altogether.

 

[dummos]

2x 560 ti's or 2x6950 would be a much better solution than 4x6770's but if i was you id wait for a price drop on 7970 or get a single 6970 and xfire later

 

[PCgamer81]

I have to tell you...

Low end cards are not meant for crossfire. If you cannot get a frame rate equal to your refresh rate with a dual card configuration, you are going to get microstutter.

Go with a single 1GB 6950 - great card it is.

 

[amuffin]

Yes you can. The only requirement is that at least 2 of the cards have two crossfire connectors like this one

http://www.newegg.com/Product/Product.aspx?Item=N82E16814150540

whoah really??!?? Are there any benchmarks of this?

 

[PCgamer81]

2x 560 ti's or 2x6950 would be a much better solution than 4x6770's but if i was you id wait for a price drop on 7970 or get a single 6970 and xfire later

+1

 

[PCgamer81]

whoah really??!?? Are there any benchmarks of this?

That is odd that it has two crossfire bridges, that would definitely indicate support for quad-fire.

But not necessarily so. Most people prefer to use both bridges with dual card configurations - as each card comes with bridge connector - as some benchmarks have suggested that you may get better performance with both bridge connectors on. I only have one in use on my 6970x2.

I scoured the internet to see if I could dig up anything about quad-fired 6770's. I could find it on 68xx line, but on the 67xx, google brought up 5 results. Pretty damning.

 

[megamanx00]

whoah really??!?? Are there any benchmarks of this?

http://www.guru3d.com/article/powercolor-radeon-5770-single-slot-quad-crossfirex-review/

Basically if it has two CF fingers, it supports quad crossfire as only one finger is needed for two way CF. Remember, the 6770 is a 5770 with an updated BIOS. When 4-way Crossfire X works properly it can be faster than two 5870s in CF. Depending on the game though the 4th card can have no, or even a negative effect. If I had to guess I'd say the the extra CPU overhead needed for 4 way crossfire as well as lack of 4-way profiles for many games explain the sometimes odd results.

 

[de5_Roy]

http://www.guru3d.com/article/powercolor-radeon-5770-single-slot-quad-crossfirex-review/

Basically if it has two CF fingers, it supports quad crossfire as only one finger is needed for two way CF. Remember, the 6770 is a 5770 with an updated BIOS. When it works properly it can be faster than two 5870s in CF. Depending on the game though the 4th card can have no, or even a negative effect. If I had to guess I'd say the the extra CPU overhead needed for 4 way crossfire as well as lack of 4-way profiles for many games explain the sometimes odd results.

:O nice link.
looks like tri-fire is the best setup with the 5770s.
power consumption and noise are the biggest drawbacks of combos like quad-fired 5770. next would be amd's driver support and cpu bottleneck on amd cpus and low end intel dual cores.

 

[swifty_morgan]

you don't always need cross fire bridges for it to work. there are instances where it works via software............ ( NO, google it ! )

 

[thently]

Dude, no offense...

Are you smoking crack?*

Just a single 5870 blows the 6770 out of the water, totally destroying it.

http://www.hwcompare.com/5808/radeon-hd-5870-vs-radeon-hd-6770/

A 5870X2 would...

... it would be total annihilation.



*If what you meant was "...two 5770's in CF...", then forgive me (even though that is still not true).

Chill Dude if you read everything and followed his link you would know he was talking 5770 Crossfire an in some games it was beating the 480 SLI so all in all 3 card setup seems the way to go if you must.

Thent

 

[PCgamer81]

Chill Dude if you read everything and followed his link you would know he was talking 5770 Crossfire an in some games it was beating the 480 SLI so all in all 3 card setup seems the way to go if you must.

Thent

"Remember, the 6770 is a 5770 with an updated BIOS. When it works properly it can be faster than two 5870s in CF."

That was what threw me off.

It should have read...

"When it works properly, the 5770x4 can be faster than two 5870's in CF - and remember, the 6770 is a 5770 with an updated BIOS."

Thanks for pointing it out.

Original message deleted.

 

[PCgamer81]

Not possible. You can't quad crossfire 6770's.

I thought that at first, but seeing as how it has two bridges per card and the 5770's could be quad-fired, I am starting to believe they can be.

 

[thently]

No prob all good

Thent

 

[PCgamer81]

you don't always need cross fire bridges for it to work. there are instances where it works via software............ ( NO, google it ! )

Straight into the motherboard and into the other card? How in the world would software pull that off?

I believe you, but I just don't see...

That's amazing.

 

[thently]

It runs all the SLI info through the PCI-e bus yes it can be done but it is slower and not sure why anyone would do this.

Thent

Oops edit Crossfire LOL

 

[PCgamer81]

It runs all the SLI info through the PCI-e bus yes it can be done but it is slower and not sure why anyone would do this.

Thent

Oops edit Crossfire LOL

Wow. Exclusively via PCI-e...

I can see why it would be slower.

Question: I am only using one crossfire bridge connector because I couldn't find the one that came with my first GPU. I have heard from some that you do get slightly better performance from having both crossfire strips in use.

Do you know anything about that?

 

[alrobichaud]

you don't always need cross fire bridges for it to work. there are instances where it works via software............ ( NO, google it ! )

Is AMD's chart wrong. Sure you can crossfire without the bridge, but only on certain cards.

 

[megamanx00]

^ Well, with newer drivers you don't need the bridge on lower end cards. For example you don't need it for the 5670 but many manufacturers put the bridge in there anyway (this was pointed it in launch reviews of the card) which is probably why there's a yellow square there. It even has a yellow square on the 6450? I've never seen a 6450 with one CF bridge.

 

[PCgamer81]

^ Well, with newer drivers you don't need the bridge on lower end cards. For example you don't need it for the 5670 but many manufacturers put the bridge in there anyway (this was pointed it in launch reviews of the card) which is probably why there's a yellow square there. It even has a yellow square on the 6450? I've never seen a 6450 with one CF bridge.

Also, I don't know for sure, but...

Perhaps it is possible that most, if not all, AMD card's can work in that manner, but AMD only lists as capable the ones that can do so without involving third party software.