SLI / CrossFire FAQs

[plznote]

Hey Maz, add the 6670 and 6570.

 

[Maziar]

Done, thanks for mentioning

 

[plznote]

 

[palladin9479]

Got a question, has anyone had any good results from using NVidia Hybrid SLI?

Here is my setup,
Asus Fforce 750a chipset with onboard GPU for hybrid use only.
NVidia GTX 285 x 2 SLI with water cooling.

Now I know those two GPU's eat lots of juice and I'd like to find a way to turn them off during web browsing / common PC stuff and only use them when I'm gaming. I was originally interested in using Hybrid SLI so that I could use the system this way. Has anyone been successful in setting this up on Windows 7 Ultimate x64?

 

[silkstone]

Anyone know if all g33 motherboards would support Xfire? i have a g33 with a x16 and a x4 pcie slot, but the motherboard specs don't list crossfire support 🙁

i would rather spend an extra couple hundred bucks to get a second video card than spend $400 to upgrade to an i5.

 

[Maziar]

Some G33 boards do,what model do you have ?

 

[plznote]

Maz, the 560.

 

[Maziar]

I was actually going to add that yesterday but we had power outage problems so I missed 😀
Thanks for mentioning,added it

 

[plznote]

Oh, sorry for sounding ignorant. 🙁

 

[Maziar]

Oh no,you didn't sound ignorant at all,I was just saying I was going to add it yesterday.
I actually appreciate that you read this topic and keep me updated in case I forget to add something,so no offense taken and I didn't mean anything bad either

 

[dogman_1234]

so Maziar...when can we expect the ATI 7XXX series?

 

[Maziar]

Don't know really but I hope they'll be out soon

 

[plznote]

I think probably Q4 2011 and Q1 2012.

 

[prolim123]

There a few things that need to be cleaned up in the description if it's to remain a sticky.

You need to change the wording of the description of Xfire, you make it sound like ATi copied nV when if anything it's nV who copied ATi and Metabyte's methods of doing multi-card graphics. nV's SLi bears no resemblance to 3Dfx's SLI in anything other than name. And SLi didn't come first in the rebirth, that was Alienware's failed ALX and XGI's volari V8 Duo. And ATi was doing their SIMFusion thing the whole time with Evans & Sutherland.

Also you need to split the solutions up, since your first example of the same cards applies to SLi but not Xfire. So it should be clearly defined which one you're talking about, you examples lets someone guess, but it needs to be explicit.
And in the memory example following it, you talk about memory and then talk about speeds. The 7800GTX is a bad example for memroy since there is athat large difference. But when mentioning memory and talking about size you should mention the size being affected and that they will disable the added memory. You're sort of mixing your ideas here. Then right after that you say you can mix/mathc brands but make sure they have the same memroy and clocks, yet right before that you imply/state they can have different memory/clocks.
For an Xfire section you should add that while the cards need to be the same underlying architecture, they can have different numbers of shaders or pipelines and still work together, like an X1900GT + X1900CF combination.

Also when talking about multi GPU benefits, rememebr to mention that one of the areas of greatest impact is also in the minimum fps, where it will usually increase min fps and smooth out dips into the lower numbers. It's an important factor that's usually missed in the discussion and is the area that would be most noticeable to people not looking simply to push large resolutions or high settings.

And when talking about does it always improve performance, you should also mention that sometimes it actually hurts performance when using the additional card.

When talking about the memory doubling myth you may wish to expand on how the memory is used and why it doesn't 'double the memory' when in Crossfire/SLi mode.

When talking about 2 midrange beating 1 high end, the thing to rememebr is that there are exception to that, like 2 GF7800GTs beating 1 GF7800GTX-512 for less money, or 2 GF8800GTS beating a single GTX or Ultra for the same money, but it depends on the situation, because there's no clear cut rule for that.

I'd get rid of the 'which is better' comment, you could discuss that with intelligent people night and day and never get and answer, and posting to any one benchmark doesn't solve that question either. So I'd pretty much avoid it unless you take the time to explore it further than a link to a single group of tests.

Also I'd avoid posting a list of cards, unless you can keep it up to date and include all the sub cards, better to just link to AMD & nV's list thus the onus is on them and not you.

BTW, what the Crossfire/SLi RAMs sections? Sounds like you're talking about the 'certified' parts. But the way its written sounds like VRAM.

If you're mentioning 'Crossfire/SLi editions' etc. you might want to mention that for AMD the boxes stamped 'Crossfire Edition' come with the ribbon connectors required to run cards in Xfire.

There's also a few spelling mistakes, but I can clean those up directly if you want.

LOL i though it is crossfire the fps game problems on a SLI Graphic card

 

[General_Terror]

A crossfire question.
What about the cards that DON'T have the additional power connector, like the 5670, 6670 etc. whose TDP is just under PCI-E's 75 Watt power limit. Won't they have power problems ?
Or does it work in this way, that each PCI-E slot has it's own 75 Watt limit ?

 

[dogman_1234]

A crossfire question.
What about the cards that DON'T have the additional power connector, like the 5670, 6670 etc. whose TDP is just under PCI-E's 75 Watt power limit. Won't they have power problems ?
Or does it work in this way, that each PCI-E slot has it's own 75 Watt limit ?

You can X-fire two sub 75 W GPU cards together, as long as they are the SAME card. No, they won't because the PCI port will supply enough power to each individual card. Each slot its own 75W limit for the GPU card it has, regardless of X-fire.

 

[Hypnotique123]

thanks Maziar for this thread.

I am in a midst of building a news system based on 2500K and AsRock Fatality Pr P67.

But I am stuck with choosing my GPU setup

1) 2 x HD 6950. this options seems to be the best in terms of cost vs performance. My only concern is I have never had SLI/CF setups and I am a bit concerned. From what I have read, the performance of 6950 CF is superb but all the talk about some games not taking advantage of the CF setup is worrying for me. Will i also need to invest in better cooling if I go with a CF setup? how about overclocking? is OCing a CF card more complicated than a single card?
also when choosing my 6950 cards, do I just go with a basic stock model or is it worth going for the more expensive cards like Asus or HIS with their factory OC and superior cooling?

2) A single GTX 580 or a single HD 6970. This option seems OK too since it allows me to add another GTX 580 later if need be.

3) A single HD 6990. I was about to go with this option but seeing how the card is being said to be noisy and hot and since there are no real improved mods in the market, I will probably not go with this option.

 

[Maziar]

I'd go with the second route.A GTX 580 is slower than 2 6950s/1 6990 but it still performs great and can max out all games on resolutions like 1080p;furthermore,as you mentioned as well,you can add another GTX 580 later on.
I'd only recommend 6990/2 6950's if you play on higher resolutions.

 

[Guest]

Hi Guys! I am new to pc building so please don't be too hard on me. I got dual GTX 570 video cards and am wondering if I i need a bridge to use them in sli? Sorry it it's a dumb question. Overall I am loving the pc building community. Thanks!

Matt

 

[Maziar]

Welcome to the forums !
Yes,you need to use a bridge when you SLI 2 cards

 

[General_Terror]

Another crossfire question. Will the Radeon 5000 series enjoy hybrid crossfire with AMD Llano and/or Trinity ? Or only the 6000 or upcoming 7000 series ?

 

[dogman_1234]

^ Ummm...Hybrid exists only with SLI and Corissfire systems....like Putting a 560 with a 5870. If you put another GPU in, the IGP onboard or on-system will be deactivated.

7xxx will be a long time to take.

 

[muckle]

Hello - been reading through the FAQ, quite informative. I noticed people post a lot of questions on their setups in this thread so I thought I'd throw out a line -

my setup - i5-750, asus p7p55d-e pro, 8gb RAM,

current card is gigabyte SOC 470
http://www.newegg.com/Product/Product.aspx?Item=N82E16814125338

My particular card (which I'd argue is the best 470) has become quite rare and would probably be quite expensive even still.

So my question is, at this point would it be worth adding an additional 470? It seems I could get one on ebay for $100-$150. I understand that it doesn't have to be the same model - so what would be the closest match? my 470s stock speeds exceed all the others - so I'd have to lower them to match the weaker one, is this correct?

Please help me make an informed decision

 

[Maziar]

Hello - been reading through the FAQ, quite informative. I noticed people post a lot of questions on their setups in this thread so I thought I'd throw out a line -

my setup - i5-750, asus p7p55d-e pro, 8gb RAM,

current card is gigabyte SOC 470
http://www.newegg.com/Product/Product.aspx?Item=N82E16814125338

My particular card (which I'd argue is the best 470) has become quite rare and would probably be quite expensive even still.

So my question is, at this point would it be worth adding an additional 470? It seems I could get one on ebay for $100-$150. I understand that it doesn't have to be the same model - so what would be the closest match? my 470s stock speeds exceed all the others - so I'd have to lower them to match the weaker one, is this correct?

Please help me make an informed decision

No,each card will operate at their default speed(sorry for the late reply)

 

[portreci]

Hello Everyone !
Can i install double nvidia quadro ?
Is that possible with SLI ?
Thanks