7970 - to Crossfire or not to Crossfire

[Maximus_Delta]

Hi,

I have a Sapphire 7970 powering a 2560 x 1440 display.

I have already overclocked and found rock solid stability (OCCT all shader complexities) on standard voltage at 1050mhz. Yes I can run it at 1125mhz with a voltage bump but the heat and noise isn't worth it.

My dilemma is that its not quite fast enough at the above resolution for BF3 multiplayer at ultra. Other games like Alan Wake on max settings do a minimum of 40-60fps while looking gorgeous but BF3 dips down to 30fps in parts which I do notice in multiplayer.

I would like to get another 7970 and crossfire, I think my Seasonic X-760 760w PSU can handle it... but I have heard of issues around micro stutter and driver problems. I am not so worried about the driver problems as those typically do get sorted out in time but what about other issues.

I would like your thoughts on whether I should go ahead and get another 7970 or just wait for a more powerful single GPU card in a years time or so if its really not worth the hassle / headaches. I have never run a dual GPU setup before.

Thank you in advance.

 

[cliffro]

I'm running BF3 with 2 560Ti's and I get no micro-stutter that I am aware of nor driver issues. Only sound issues, as in loud as heck(I have a very aggressive fan profile set to keep the heat down)

But with those we're talking an obscene amount of money and your issue with Noise and Heat will not be solved with two, in fact it could be louder than 1 with the voltage bump and warmer too.

So try overclocking more and see if it alleviates the slow downs, it if does to an acceptable level, wait for a while, if not, then you could consider a second, or a lower resolution monitor(which would be a lot cheaper than another 7970).

 

[hellfire24]

go ahead!

 

[Maximus_Delta]

I'm running BF3 with 2 560Ti's and I get no micro-stutter that I am aware of nor driver issues. Only sound issues, as in loud as heck(I have a very aggressive fan profile set to keep the heat down)

But with those we're talking an obscene amount of money and your issue with Noise and Heat will not be solved with two, in fact it could be louder than 1 with the voltage bump and warmer too.

So try overclocking more and see if it alleviates the slow downs, it if does to an acceptable level, wait for a while, if not, then you could consider a second, or a lower resolution monitor(which would be a lot cheaper than another 7970).

Thanks for the info and that is good to hear that you are not observing micro stutter on your Nvidia setup... are ATI cards worse when it comes to this tho?

I have tried overclocking my card to the max. I can get it stable at 1175mhz with more than just a small voltage bump with a very aggressive fan profile. But the fan is literally screaming loud, temps over 90 degrees and its chucking out a huge amount of heat. Basically its not practical to run it like that and I would have to get a water block for it if I wanted to do so which is an expense and hassle in itself. In the end its only 12% more speed than I have now and wouldn't change the situation, minimum fps go up from 30-33 to 33-36, its still not smooth

I bought the monitor at the same time as the graphics card. Both were over 500 USD... so that's why I am thinking perhaps I should just bite the bullet and spend another 500USD on a second 7970 and get the setup I really wanted to begin with... which is a smooth near 60fps at 2560 by 1440. I've already spent 1000USD trying to get that not including the rest of my PC.

However I am worried I am going to get this second 7970 and it's not going to work properly or I will have enough issues with it to make me regret it...

 

[Maximus_Delta]

go ahead!

Do you have a Crossfire setup working well? Did you have any issues with it? Any regrets?

 

[SkyWalker1726]

keep in mind that :

1-90 Degree , is HOT and keep in mind that when Crossfired , the Top card Temp will increase

2-BF doesn't quite work well with oCed GPus ( just head to battlelog Forums , there are many topics about that )

3-Crossfire works quite well in BF

4-if u want 60FPS , what other option do u really have ? u already have the most Advanced and powerful Single GPU out , so the only way to increase your framerate is to crossfire with another one

5-7xxx series is still new , and new-er Driver will keep improving it's performance ( there was an update for BF also , that mentioned improving compatibilty with 7xxx series and ivyBridge )

6-7xxx in PCie3.0 and ur mobo is PCie2.0 so u might not be using all of it's HorsePower til ivybridge comes out ( although i doubt it would be such a boost .... )

 

[hellfire24]

Do you have a Crossfire setup working well? Did you have any issues with it? Any regrets?

no i don't lik multi-gpu setups but a lot of people are using them and are happy.

 

[esrever]

wait till nvidia launches the 6XXs. the drivers are not official yet so the crossfire with the 7970 is less than what you'd expect. Wait till the official drivers and a price drop once the nvidia cards come out.

 

[Maximus_Delta]

Ok thanks for the information, I'll get another one and see how it goes.

 

[expensivecomputer]

keep in mind that :

1-90 Degree , is HOT and keep in mind that when Crossfired , the Top card Temp will increase

2-BF doesn't quite work well with oCed GPus ( just head to battlelog Forums , there are many topics about that )

3-Crossfire works quite well in BF

4-if u want 60FPS , what other option do u really have ? u already have the most Advanced and powerful Single GPU out , so the only way to increase your framerate is to crossfire with another one

5-7xxx series is still new , and new-er Driver will keep improving it's performance ( there was an update for BF also , that mentioned improving compatibilty with 7xxx series and ivyBridge )

6-7xxx in PCie3.0 and ur mobo is PCie2.0 so u might not be using all of it's HorsePower til ivybridge comes out ( although i doubt it would be such a boost .... )

Hi im curious as to what you mean by " 2-BF doesn't quite work well with oCed GPus ( just head to battlelog Forums , there are many topics about that )".
I attempted to search that battlelog forum but haven't been successful.

Are you saying stability/errors when not "work well" or not proportional scaling in terms of FPS relative to OC % (ie. overclock by 20% but only get 10% more fps). Please link if possible to what your mentioning.

 

[bystander]

The good news is that your motherboard has 3 slots between the 1st and 2nd PCIe slot, that means the top card won't get much hotter than the lower one, if at all. You also have a resolution where it has use of the extra power, although two 7950s might have been a better choice for your res, but that also means you can run the 7970's at stock and have plenty of power and not have to deal with the extra noise.

 

[Maximus_Delta]

The good news is that your motherboard has 3 slots between the 1st and 2nd PCIe slot, that means the top card won't get much hotter than the lower one, if at all. You also have a resolution where it has use of the extra power, although two 7950s might have been a better choice for your res, but that also means you can run the 7970's at stock and have plenty of power and not have to deal with the extra noise.

Thanks, yes got the second 7970 now and did see my motherboard has a slot between the two.

I intend to run both at 1050mhz on the core which doesn't need any more voltage and doesn't seem to increase the noise much.

I agree, if I was able to turn back the clock I would have got 2x 7950s as I feel that would of been sufficient and quite a bit cheaper.

I'll post back here when its all done and tested over the next few days to confirm its working properly and I don't have any regrets about going down this route.

 

[Maximus_Delta]

The good news is that your motherboard has 3 slots between the 1st and 2nd PCIe slot, that means the top card won't get much hotter than the lower one, if at all. You also have a resolution where it has use of the extra power, although two 7950s might have been a better choice for your res, but that also means you can run the 7970's at stock and have plenty of power and not have to deal with the extra noise.

Thanks, yes got the second 7970 now and did see my motherboard has a slot between the two.

I intend to run both at 1050mhz on the core which doesn't need any more voltage and doesn't seem to increase the noise much.

I agree, if I was able to turn back the clock I would have got 2x 7950s as I feel that would of been sufficient and quite a bit cheaper.

I'll post back here when its all done and tested over the next few days to confirm its working properly and I don't have any regrets about going down this route.

 

[SkyWalker1726]

Hi im curious as to what you mean by " 2-BF doesn't quite work well with oCed GPus ( just head to battlelog Forums , there are many topics about that )".
I attempted to search that battlelog forum but haven't been successful.

Are you saying stability/errors when not "work well" or not proportional scaling in terms of FPS relative to OC % (ie. overclock by 20% but only get 10% more fps). Please link if possible to what your mentioning.

search for "Green Flicker" or "Red Flicker" , i used to OC both of my 6870 to 950mghz but it caused that kind of flicker and disabling it solved the problem , i didn't oc after that , might have been fixed with the released patch tough ...

 

[Maximus_Delta]

After some testing the top card is getting pretty hot when stress testing. I was using 1050mhz on both the cores and it was hitting 93-94 degrees. Reduced the core speeds to 1025mhz, still getting to about the same temps on the top card though.

In 3DMark11 my score improved by around 70% and BF3 on ultra is giving a constant 60 fps with V Sync on with no immediately apparent adverse effects. So at this preliminary stage it has done what I hoped it would do.

 

[bystander]

You might want to make your bottom PCIe slot the primary slot within your bios if you can, then connect the monitors to the bottom card. That might help with the temps on the top card.

 

[ravesaint5]

Do you have a Crossfire setup working well? Did you have any issues with it? Any regrets?

I have 2 6950's running on crossfire. I regret going with ATI for multiGPU. I myself get micro-stutter even with hyperthreading on the 2600k turned off. I run fraps to check my FPS, it tells me I have 80+ FPS but you can see the lag. It runs around 40-50 even though it says 80-90-100+.

My brother is running 2 GTX 470's and is getting the proper shown FPS in fraps. The FPS counter works properly Nvidia for BF3. He gets lower FPS than I do by around 10-20 FPS, but his games runs A LOT smoother than mines.

If you want to run a multi-GPU setup for BF3, I suggest Nvidia. Better drivers as far as I can tell.

 

[johnsonma]

I have a single sapphire 7970 and while it is a beast of a card I have been having driver issues. I am not disappointed at all since i bought the card right when it launched. The last driver updated helped IMMENSELY and I can't really complain now. I get the occasional crash to desktop on witcher 2 but no more BSOD and games freezing and crashing nonstop.

The driver support will catch up soon and then I will most likely go to a crossfire setup but not until then.

 

[Maximus_Delta]

You might want to make your bottom PCIe slot the primary slot within your bios if you can, then connect the monitors to the bottom card. That might help with the temps on the top card.

Thanks, that's a good idea, I tried it. In my BIOS I was able to set the x8 slot as the primary. Reconnected the monitor to the bottom card, it worked fine until it got the "Starting Windows" screen at which point it just hangs... Any idea why it might be doing that?

 

[Maximus_Delta]

I have 2 6950's running on crossfire. I regret going with ATI for multiGPU. I myself get micro-stutter even with hyperthreading on the 2600k turned off. I run fraps to check my FPS, it tells me I have 80+ FPS but you can see the lag. It runs around 40-50 even though it says 80-90-100+.

My brother is running 2 GTX 470's and is getting the proper shown FPS in fraps. The FPS counter works properly Nvidia for BF3. He gets lower FPS than I do by around 10-20 FPS, but his games runs A LOT smoother than mines.

If you want to run a multi-GPU setup for BF3, I suggest Nvidia. Better drivers as far as I can tell.

I haven't observed any issues in BF3 at all with micro stutter. Just a constant 60fps. Have you set V-Sync to on? I read somewhere that this helps avoid any micro stutter and you don't need any more fps than your monitors refresh rate.

 

[bystander]

Thanks, that's a good idea, I tried it. In my BIOS I was able to set the x8 slot as the primary. Reconnected the monitor to the bottom card, it worked fine until it got the "Starting Windows" screen at which point it just hangs... Any idea why it might be doing that?

You might have to go to safe mode and uninstall the drivers or go to the device manager to remove the cards, then reinstall the drivers after rebooting into windows normally.

 

[Maximus_Delta]

I have a single sapphire 7970 and while it is a beast of a card I have been having driver issues. I am not disappointed at all since i bought the card right when it launched. The last driver updated helped IMMENSELY and I can't really complain now. I get the occasional crash to desktop on witcher 2 but no more BSOD and games freezing and crashing nonstop.

The driver support will catch up soon and then I will most likely go to a crossfire setup but not until then.

Yes I am still having some odd problems too. For example I can't see the temps of the second card in either Afterburner or Hardware Monitor. The latest drivers seemed to help things overall but at the same time completely broke Alan Wake in CrossFire. It's quite a good strategy on their part, the more enthusiast user base is a better beta test bed for ironing out these driver issues. It's a shame the drivers are almost always a issue but it is almost as bad with Nvidia. Still I would rather have the card now and enjoy it where it is working properly than wait until the drivers are perfect.

 

[Maximus_Delta]

You might have to go to safe mode and uninstall the drivers or go to the device manager to remove the cards, then reinstall the drivers after rebooting into windows normally.

Followed the above and it worked. The bottom card is now the primary, all working fine in Windows and back at the 1025mhz overclocks.

So far so good, the top card is shut down as in 2D mode now and I can instantly see the bottom card is on at idle at least 5 degrees cooler because its getting the unrestricted feed of cold air now from my bottom fan intake.

I'll do some testing, OCCT and games, and see if the temps are lower on the top card / better distributed. Thanks for your help!

 

[Maximus_Delta]

Ok I did some testing in OCCT max shader complexity which seems to generate the most heat... with the lower card as primary the temps on the top card have come down by 1-2 degrees. Its running 91-92 degrees now as opposed to 93-94 degrees. I am slightly more comfortable with that.

The max temp on the lower now primary card has gone up from 86 to 88 degrees. So it looks like I have swapped 2 degrees of heat in favour of the lower card and improved the balance between the two cards.

Good tip! Thanks

 

[bystander]

Keep in mind that OCCT is considered a heat virus by manufacturers. It shouldn't ever get that hot in normal gaming.