SLI / CrossFire FAQs

[8350rocks]

Thought this would be somewhat relevant regarding Crossfire:

http://hardocp.com/article/2014/07/23/gtx_780_oc_6gb_vs_r9_290x_4gb_overclocked_at_4k/11#.U9AA27EjaGQ

 

[8350rocks]

Actually, if we wanted to be technical, SLI was developed by 3DFX for their voodoo cards back in the 1990s, and NVidia acquired the rights to 3DFX and the technology for SLI with it.

 

[nukemaster]

Scan Line Interleave.

Good times.

3DFX was ahead of its time in many ways.

 

[8350rocks]

Scan Line Interleave.

Good times.

3DFX was ahead of its time in many ways.

Yes, they did so many good things, they were just outplayed by Nvidia...sadly...

 

[Xeja1]

I have 3way Crossfire (R9 290s) in my set-up, and i have a question.

When i go into the Control Panel to turn on Crossfire, it gives me 3 options, 3 GPU (some numbers), 2 GPU (some numbers), and then 2 GPU again (with some more numbers).

Whats the difference between these options?

 

[nukemaster]

Can you post a screen of your options.

With 3 card you are going to want to use all 3 GPUs to get the best performance.

I hope you have a beast of a system to feed 3 cards

 

[Xeja1]

Underneath the 2 buttons for enabling and disabling Crossfire, their is a drop down box that has the 3 options i mentioned before.

3 GPUs (0 6 12)
2 GPUs (0 12)
2 GPUs (0 6)

Perhaps it has to do with how the frames are rendered? The thing is, i cant find any official documentation on this anywhere. Seems weird.

Yes, my system is just fine Plus it has 7680x1440p to push, so its not lazing around either lol

I pair the GPUs with a 4930K and 1866 Memory on the ASUS Rampage IV X79 board. I bought the cards almost on day 1 of their release, so theyre all custom cooled with the arctic coolers that were very popular for a bit.

 

[nukemaster]

I do not see any official documentation and see users just wondering about it as well.

I may be worth shooting an email off to AMD about this one.

With 3 GPU's you should have best performance. and with that resolution to push, it is good to have all that power.

 

[Sammy_84]

Hi there,

I would like to crossfire 2 x R9 280X's - The mb I would like to use is Maximus VII Hero. The AGP ports run @ 8x in duel mode. Will this be sufficient to take advantage of the cards or am I better off trying to find a board that will run 2 x 16x AGP ports? This limits my options a bit as you pay a fair bit more and I like the Hero.. is it necessary? Many Thanks!

 

[8350rocks]

You are fine at 8x. That is the same as PCIE 2.0 x16. Which makes good use of those cards. You should be fine.

 

[Resetes12]

Can I crossfire a Tahiti XT with a Tahiti XTL? (HD 7970 with a new R9 280X)

 

[8350rocks]

Yes, you can crossfire those 2.

 

[Scott Leess]

i have the radeon r7 260x and a r7 265 but they wont crossfire together can anyone comment on my post
help please

 

[nukemaster]

please help me,,,i have nvida 8600gt but not work in asrock h61m-vs3......??????

Please check to ensure you have the latest bios for the board. Sometimes you may need the secure boot option off for some cards as well.

It is best to create your own thread for this type of issue.

i have the radeon r7 260x and a r7 265 but they wont crossfire together can anyone comment on my post
help please

I am not 100% sure you can crossfire those cards. They seem to have different cores.

Radeon R7 260X = Bonaire with 128-bit memory controller.
Radeon R7 265 = Pitcairn with a 256-bit memory controller.

Even if it worked, it would be like crossfiring a 5770 with a 5870. You may get it to work, but may perform worse than a single card.

I would Contact AMD to be 100% sure those cards can work together in crossfire.

 

[Sn1992]

I crossfired my r9 280x vapor x with my new xfx black r9 280x but i dont get any fps gains more than 10 more than single card in battlefield 4
Tried dissabling ulps
I dont know how to resolve this issue



Complete specs


Processor - INTEL i7 4790k devils canyon(haswell refresh) @ 4.6ghz on 1.26v
Motherboard- ASUS REPUBLIC OF GAMERS MAXIMUS VII HERO
RAM- G.SKILL RIPJAWSX 2x4GB 2133mhz
Cooler- corsair h80i liquid cooler with noctua nt-h1
Graphic card- SAPPHIRE R9 280x VAPOX 3gb xfired with r9 280x black edition
PSU- COOLER MASTER silent pro M 850w
CABINET- corsair air 540 HIGH AIRFLOW (with 3x CM jetflows and 2x CORSAIR AF140)
Lighting- NZXT HUE RGB Controller
Fan controller- NZXT GRID fan controller
Harddisk- WD caviar green 500Gb
Ssd- 120gb 840 evo

 

[nukemaster]

What is the actual frame rate. if you went from 50 to 60 that would sound like Vsync.

Your system specs look more than enough for anything.

Please ensure that the latest drivers are in use and even try the beta ones since they tend to get crossfire profile optimizations first.

I would fine it extremely unlikely that you have a system bottleneck with the cpu or gpus.

 

[Sn1992]

It would be strange if anything bottlenecks as these are high end gpus and one of the best cpu
My frame rate was 55 avg and now its 70 avg

 

[nukemaster]

For the sake of completeness can you please try some other games or benchmarks.

You may get more help making a thread about his actual problem because I am not sure how many users are active in this thread.

 

[Sn1992]

Tried making a thread bug no answer

 

[nukemaster]

I am sure you will get some. It is the weekend so maybe people are away.

 

[chris25]

How does this happen that this was posted in 2007 but this guy foreseen r9 series and tita!! How??isn't it creepy!?!?!!

 

[chris25]

The original post was in 2007 when he posted the r9 series and all that..how does it made possible? Creepy!!freaking post!! 2007 anf he was able to enumerate all 2013-14cards!!

 

[Maziar]

haha,Actually I edit this FAQ time to time.Back in 2007,it was notably different with fewer models.

 

[Scott Leess]

hers a question for you
im getting my second gpu to run crossfire
my main gou asuys r7 260x is over clocked ( OC edition)
my 2nd gpu is not over clocked
would that make a diffrance?

 

[8350rocks]

hers a question for you
im getting my second gpu to run crossfire
my main gou asuys r7 260x is over clocked ( OC edition)
my 2nd gpu is not over clocked
would that make a diffrance?

No, you should be just fine. I would recommend trying to keep the manufacturers and clockspeeds close, but it is not necessary for crossfire to do so as long as the cards use the same GPUs.