ATI HD 6970 Crossfire question

[cardician]

Hello,

First, I apologize but this post might be long. I've never Crossfired or SLId cards before so I have a few questions regarding my new setup.

So I just built a new system largely based on the Tom's Hardware build of the month.

Asus P8P67 Deluxe mobo
8gb Gskill DDR3 1600 ram (might up to 16gb soon)
2 ATI HD 6970 in crossfire
i7-2600k chip at 3.4ghz (not OCed yet)

So I put everything together and amazingly everything seems to be working (I almost always have some issue on a new build). Everything is at stock at the moment while I put the computer through it's paces to make sure there are no issues. Then I will begin the fun of OCing things.

However, this is my first time crossfiring and I'm not sure everything is working properly. I went ahead and put both crossfire bridges on the cards. They are installed and running at x8/x8. Both cards do work (I ran them independently earlier in the build process and got video out of both). Here are the weird things I've encountered though.

When I go into the catalyst control center where you can overclock the cards, it shows the first card running with stats as you'd expect. It's temp at idle seems to be in the 40s C and so on. I can also take the fan off auto and ramp it up and hear it get louder. However, when I select the second card on the drop down all the stats drop to 0. As if it knows the card is there but at the same time it's not doing anything. If I ramp it's fan up I also didn't hear an increase in noise. I also looked in GPUZ and don't recall it showing as crossfire set anywhere but I'll have to look more closely. I wasn't looking for it and could have missed it.

Some more oddities are in the crossfire settings. I checked the box to enable crossfire, but nothing visibly happened. Don't know if anything is supposed to of course. Then when I click on the identify GPU buttons, nothing happens (well a 1 does appear on my screen). In the other tab dealing with crossfire where there is a little box that's supposed to show information, nothing is displayed. It also has an identify GPU button that does nothing. Can anyone tell me what's supposed to go on at these screens or is that working properly?

Finally, I will say that in the CCC taskbar icon I enabled it to show crossfire status or whatever when applicable and then when I ran 3d Mark 11 the ATI crossfire icon did appear in the upper right corner. Also, my performance preset test in 3d Mark 11 did return a score about 100 points better than the benchmark for the Alternative $2000 PC. I consider that a sign that perhaps crossfire is working because my build is based off the latest Alternative March 2011 $2000 PC build. So if I'm scoring a bit better than they did on the non-OC benchmark, I guess both cards must be crossfiring. Another weird thing though is that in GPUZ, the temp for the main card rose to around 80C during 3dMark 11 but the second card did not seem to get very hot at all. Is that to be expected or should they both get hot. I definitely need to do some more testing.

So, in summary, I guess crossfire is working but I'm wondering about some of the oddities in the CCC and was hoping someone could tell me if what I'm seeing is correct or if something might still be wrong.

 

[wolfram23]

Easiest thing to do is download MSI Afterburner. I use it all the time to monitor my cards, really love it.

Run whatever you want - game, benchmark - and then check the GPU usage charts in Afterburner. Obviously if the 2nd card shows no usage then something isn't right.

FYI you should try testing if 1 bridge helps performance or doesn't change it... for me 2 bridges had issues (5850s).

GPUZ should show Crossfire on the main tab at the bottom.

And finally what is your 3dMark 11 score? If CF is working I'd assume around 9k

 

[cardician]

Easiest thing to do is download MSI Afterburner. I use it all the time to monitor my cards, really love it.

Thanks so much for the reply and suggestion (and for suffering through my long post)! I will definitely download MSI Afterburner when I get home. Sounds like it will really show me what I couldn't quite figure out from GPUZ. Does it matter that I'm not using an MSI card? Mine's an XFX.

FYI you should try testing if 1 bridge helps performance or doesn't change it... for me 2 bridges had issues (5850s).

I will look into the 1 bridge thing. Main reason I went with both was because I wasn't sure where to put just 1. Does it matter? Or does either position work?

GPUZ should show Crossfire on the main tab at the bottom.

Yeah, I have to look more closely at GPUZ when I get home today. I didn't notice it saying anything last night, but again I didn't look closely as I didn't know about it until today.

And finally what is your 3dMark 11 score? If CF is working I'd assume around 9k

My score was 9500 something (can't remember exact number and 3dMark 11 would crash whenever it tried to post the scores online) with nothing overclocked and a build very similar to the March 2011 Alternative $2000 build. They got 9472 on their non-OCed build so I'm assuming since I scored a bit better it must be working.

Really, as I mentioned, I assume it is working in crossfire, but it just seems really weird to me the way some of that stuff in the CCC appears. The Identify GPU button does nothing that I can see or understand and in the OCing part of the CCC selecting the 2nd card doesn't seem to show any stats like it does for the first card. It's as if it knows it's there since you can select it but it can't really detect it or it's not being used. But I guess it's nothing to worry about since I seem to be scoring properly. I'll have to run some more in-depth tests tonight and see what happens. I'll try turning crossfire off and benchmarking among some other things. Plus it sounds like Afterburner will really show me some useful information to help set my mind at ease.

 

[wolfram23]

Yeah CCC is a bit screwey. The identify GPU thing, as far as I know, is meant for if you aren't using CF and have monitors hooked up to both GPUs.

I think that for some reason it always shows 0mhz at idle on the second card... I know I've seen that before but I haven't really looked lately. MSI Afterburner will show you the real speed though. Should be like 300/900 on the second card I think (and 157/300 on primary).

Also no it doesn't matter that you have an XFX. I use Sapphire cards and have overclocked them with Afterburner. Oh, one thing, if you use Kombustor to test your cards (comes with Afterburner) it doesn't seem to use crossfire. Better bet would be to use FurMark. Also, CF only works with fullscreen so windowed mode is single card.

 

[cardician]

Awesome, thanks so much again for the response! You've been a huge help. You've answered everything I was worried about and put all my fears to rest I'd say. That was my biggest concern, that CCC showed my second card as being 0mhz among some other things so I was worried that something was up even though certain tests did seem to indicate crossfire was running.

Thanks again. I'm looking forward to getting home and using Afterburner. Plus it sounds like it'll be a better way to OC my cards rather than using CCCs controls.

 

[cardician]

Best answer selected by cardician.

 

[wolfram23]

Glad to help.

And yeah Afterburner is better. All you have to do is unlock the card in CCC's Overdrive tab, and also edit the Afterburner config file - it says "allowunofficialoverclock = 0" and it needs to be changed to a 1 so that you can exceed CCC's limit