Call me crazy but I don't think the crossfire bridges are the problem. I don't think they were ever an issue. AMD designed these cards to use one crossfire bridge and I'm sure it wasn't an oversight that two were needed instead of one. I can't explain the issues in that old review, but there were plenty of people running crossfire even in those days at those settings without any graphic anomalies or issues. I wish I could explain the nature of PC Gremlins, but occasionally strange things happen on some setups that can't and won't be duplicated again on the exact same setup for someone else.
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Radeon HD 7970 CrossfrieX Issues
- Thread starter Dan_D
- Start date
There is no such thing as "computer gremlins." That's an explanation about as accurate as religion is. It is what people use to fill i the blanks to explain what they can't explain or what lies out of the scope of their understanding and knowledge.
It can be explained by manufacturing variances and tolerances. Some manufacturers have loose specifications and tolerances which in electronics is the opposite of firearms. A loose firearm sacrifices some accuracy, but can gain reliability by being loose. Dirt and contaminants aren't going to screw up and prevent opperation. Electronics are generally not like that. This is why buying quality components is so important. When people see a cut rate motherboard manufacturer sell something with a lot of features for a lower price, they think it's a bargain. What they don't understand is that they are getting SATA ports that fall off, coil whine, feedback through the audio system, EMI problems, and all kinds of issues. Insufficient QC allows for too much variance as some parts get through which don't conform to specification. There are many stages which that can happen during a products construction.
There are plenty of examples of crap that made it through. Board manufacturers were using capacitors which wouldn't perform to the specifications required by the design of the board. They were sold capacitors that were basically not spec'ed for the job and they used them because they were cheaper. This bit them all in the ass when they failed prematurely and started bulging. Crappy VRMs on the GeForce Ti 4200 had them dying in droves. People often bitch about the coil whine on several NVIDIA cards. I've heard the flyback transformer on a number of cheaper Chinese made TV's back in the CRT days. I could hear a cheap TV on mute from across the sales floor at Best Buy and it hurt my ears.
I'm not singling any one company out but some are definitely more frequent offenders than others. Some manufacturers cut it exceptionally close to the spec and don't leave room for components to be stressed beyond that spec. When you do that, or when you use cheap components whos performance is all over the map, especially in specific conditions then you get abberations in performance and functionality. Hence environmental issues, and variances with specifric configurations. The problem is that without dissecting a product and being an electrical engineer, one cannot always or even usually be certain of who's cheap corner cutting is responsible for the issue. In my case if anyone did that it was probably AMD or the reference board maker given that I tried it on two top end ASUS motherboards of totally different design and one EVGA board. An older board yes, but also a top end design for it's day. All three couldn't be more different in construction, component selection and what they were QVL'ed with. Three sets of memory modules etc. all in 3 perfectly stable configurations produced the same precise problem. Hard lock while gaming in less than an hour. Heat and other factors were ruled out.
Dan, I had a feeling you or someone else would jump on that. I use that term loosely to explain things that are beyond the scope of diagnosis. There are so many factors in electronics that can cause problems and without the right test equipment, you'll never see it. This is coming from someone that has done electronics repair for years. I'm quite familiar with quality standards and mil spec very well. My point is that the average person may not have diagnostic equipment to troubleshoot every single voltage fluctation, component, ripple, etc. Sometimes there are things that just don't work for one person and do for another even with the exact same components. Do I believe its a fairy or voodoo at work? No not all, but I believe sometimes bad experiences just happen to some people and certain combinations of hardware and/or software, hence my use of for lack of a better word to describe such strange phenomina, PC Gremlins.
And please don't go there with religion. You may choose not to believe but I do and that's entirely off the subject although I know you were trying to make an anology. I just don't agree with your anology.
And please don't go there with religion. You may choose not to believe but I do and that's entirely off the subject although I know you were trying to make an anology. I just don't agree with your anology.
It was an analogy. Specifically relating to the sheer number of religions out there. They can't all be right. My point is that people tend to use their gut feelings, emotions, and imaginations to fill in the blanks on things they can't explain or understand. They do this with electronics for some reason. Hatred for one brand or another, undying devotion to a particular brand, misplaced trust, etc. You see people tend to look at these brands and parts almost with religious zealotry. The video card subforum is the perfect example of this. It's even worse than the CPU forums are.
The bridges probably are not the issue. All I know is that if you run crossfire with the 7xxx series with eyefinity you get crashes. One monitor stuff is fine. I posted the stuff about the bridges just to explain that, AMD has admitted when running high resolution in crossfire the crossfire bridge can't handle the bandwith required so they use the PCIE buss as a work around. Could this be the cause of the problem I don't know. But maybe they just have not tuned the drivers yet to handle the additional bandwith yet. The extra data on the buss could be interrupting or delaying stuff and you get a hang. When I get home I may do some testing by upscaling a custom resolution to my monitor and see if I can get a crash with one monitor.
Using the PCIe bus is probably the issue quite honestly and it may come down to driver issues doing that.
Bees
[H]ard|Gawd
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Hmm... To test this, have you thought of turning down the display resolution on your monitors and seeing the results? It may be a simpler option than sourcing multiple, smaller monitors.
No problem Dan. I understand and agree with most of what you said. I have no brand loyalty to any PC parts.
I will not run my monitors at a non-native resolution. It looks TERRIBLE. My monitors don't have a scaler in them anyway. Yes you can do it through the driver, but that's just adding another variable into the mix. That's not an option. I agree it would be an interesting test, but if that's the fix, it's not a fix I'm willing to use. I'm also not going with smaller monitors. If AMD can't deal with the resolution I'm running, then I'll go NVIDIA. Simple as that. And anyway, the cards are out of my system at this point. I've got one GTX 680 4GB in my system and I hope to grab another tonight when I return my Radeon HD 7970 to Microcenter.
It isn't resolution exactly that's the problem. It's that the cards are commmunicating to each other through the PCIe bus. At a low enough resolution they won't do that, but that's not an option for me. And running CrossfireX communication protocols over the PCIe bus could make them more sensitive to clock speed variances, PLX chips, chipset / CPU variances and other issues than if they were using the bridges alone.
I was going to use one 1080p monitor and send it higher resolutions in increments. The monitor should down scale it. If I find it crashes I will note the resolution then test with 3 monitors in eyefinty and lower the resolution in increments. I want to see if there is a crossover point at which you get crash vs resolution. The only problem Is my crashes don't happen at a given time frame so this may take a while testing at each resolution.
Mass Effect 3 was very predictible in crashes for me. I could do the multiplayer and complete 2 matches without an issues. I never could complete a third. It takes about 20 minutes per match so I typically ran into the problem just under the hour mark, and no sooner than 40 minutes on the ASUS boards. On the EVGA it took about 30 minutes. That was one thing that really sucked about this whole ordeal. Testing took a long time. So duplication of the problem was never quick or almost never quick. So it dragged out a lot longer than I wanted it to.
Somewhat off topic, but nVidia limits the pixel clock over DL-DVI to 400MHz when running in SLI. Now, the only time you see this mattering is 1440p+@100Hz+, but it is interesting. When contacted about it, nVidia claimed it was a hardware limitation of the SLI link. AMD limits DL-DVI to 330MHz always (even outside of CFX), but with custom drivers you can remove that limit (even in CFX). Nobody has had success doing that with nVidia, which makes it seem like AMD is indeed using PCI-e bandwidth between the cards while nVidia isn't. Or something like that.
Note that this doesn't really change with multi-monitor setups as far as we can tell, but each output has it's own pixel clock.
Note that this doesn't really change with multi-monitor setups as far as we can tell, but each output has it's own pixel clock.
Well if the article is accurate about 2560x1600 is the most you can do per bridge. So theoretically I'd be fine on one or two monitors. Three would cause them to communicate over the PCIe bus. I wonder if there is some kind of negotiation type protocol that cases them to switch to one or the other dynamically. If so that could definitely be a problem. Basically the game starts and it communicates over the bridge, then locks up because it suddenly switched to PCIe. I don't know. The fact is we don't know enough about how the driver handles this to make any real headway toward further narrowing down this problem. All we can do is speculate. But this bridge bandwidth issue does definitely explain how I could be fine on one monitor, but unstable on three. Three monitors at 1920x1080 or 1920x1200 are almost certainly the most common Eyefinity configurations out there. These fall well short of the bandwidth limits of three 2560x1600 panels. It's still more than 2560x1600, but I suspect that's not a hard number. But rather, an "about" value. So each bridge can handle roughly 2560x1600 pixels, but that's not exact. 5760x1200 or 5760x1080 is over the 5120x1600 pixels two 30's would require.
And I'm not sure if that's why NVIDIA does what they do with connecting monitors to other cards in 2-Way, 3-Way SLI and so on. However I suspect it's easier on the card's DACs than pushing all that shit through one card. The hard PCB bridge in 3-Way and 4-Way SLI is more expensive than flexible bridges, and I wonder if they use it because they can push more bandwidth with those.
Omegas
[H]F Junkie
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Have you tried dropping the resolutions and eye candy to see if it becomes stable?
Again, no. I will not do either. Eyecandy in the game isn't going to be an issue if the game and system are stable. On one card it is, on two cards it is (after the BIOS flash of both cards) with only one monitor enabled. So Eyecandy isn't the problem, especially when frame rates and performance isn't an issue for it. And again, even if dropping the resolution does fix it due to CrossfireX bandwidth limitations over the bridge, that's not a fix I'll accept. That right there would force me to go with NVIDIA cards if that were the case.
Omegas
[H]F Junkie
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It was more for a trouble shooting technique rather then a fix, wasn't sure if you were still doing that or not. If you dropped the eyecandy and the res to 5760x1200 (I assume those 30's have enternal scalers) and it still had problems, then you know its not the bridge capacity. Just throwing that out there.
I agree we don't know enough on how this works. Even if we did what can you do to fix it?
A.) Hope/Wait for AMD to fix it in a driver.
B.) Disable Eyefinity and run one monitor.
C.) Disable Crossfire and run eyefinity.
D.) Buy a Nvidia card.
On a side note I think why Dan is seeing the crash happening on a shorter time frame then me is because of bandwidth issue/theory. He is running a higher resolution with his 2560x1600 screen compared to my 1920x1080 screens. This would explain why stuff works on a single screen.
Anyways it looks like I am stuck with option A. My Old lady ring my neck if I bought new cards. Also Dan let us know how the 680's work out and thanks for the help. I knew I wasn't going crazy LOL! I am done for now until new drivers come out. I will post back when new drivers come out or I hear anything.
I hope you do follow through on this, it's a good idea.
And for Dan, I also hope you let us know how the 680s work for you. I'm assuming you'll be benchmarking the shit outta them, yes?
The Dell 3007WFP-HC does not have an internal scaler which is why they have the least amount of input lag of the 30" panels that I know of. So I'd have to do scaling through the driver which introduces a new variable.
There really isn't much we can do at this point.
Not really. I may do some benchmarking but I'm not a benchmark whore. I usually fire up the cards and compare my numbers from FRAPS to what Brent sees in video card evaluations and call it good.
The GTX 680's are in right now and so far so good excluding one thing. Apparently Mass Effect 3's menus are broken in NV Surround but work fine in Eyefinity. WTF? I've got to reinstall BF3 and I don't have anything else installed right now as the system has a pretty fresh OS on it now. Actually, I do have Steam games on here. I do need to set Steam back up, but I do still have all the Steam apps. So Batman Arkham City is on here. Sweet, I can see it with PhysX enabled. Amidst all this I had to get a SATA 6G backplane for my 800D as all but one SATA port in my original back plane is toast. I also ordered a USB 3.0 front panel upgrade kit since my 800D is one of the early ones and didn't have that.
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Well I have always been that wayI know if I had 2 I would want 3 it would have happened probably a week after I got the 2 installed. At least I saved some cash by there on sale lol.
As for why 3 well I like to game at 7680x1600 where I can. I figured 2 will not have enough power to drive that resolution. Plus I liked my tri fire with the 6990 and 6970. I know a lot of people moan about Tri fire but it worked for me specially at high resolution.
Plus hey I get to play with a new build which is always good. I will try to do a build log never done one before. But I have a nice TJ07 case I use I have sprayed black the inside and did some mods to it as well..
http://forums.overclockers.co.uk/showthread.php?p=22544673#post22544673
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No one can really answer that. I had a ton of problems but not everyone will. It seems to me that NVIDIA cards and drivers are less problematic on the high end, but that's just how it seems to be. That certainly has been my experience with this generation. That does not mean you will have problems or that NVIDIA is necessarioly better than AMD overall.
Non reference cards of ASUS design. Not surprised that's working for you. In fact I'd be quite surprised it they weren't. And I did consider going that route given all my issues. But gone are my mini-DP to dual-link DVI adapter problems and games seem smoother than they did even during the time CrossfireX did work. So for me I think I made the right choice, I just wish I could have gone with my original plan as it would have been less time consuming and less costly.
I just now found this thread because I have been experiencing the exact same issue in a very similar configuration since the 7970 launch. I'm running 2 Sapphire reference 7970s purchased a launch plus an MSI Lightning 7970 (bought later) which gives me 4 DP outs to drive 3 27" 3d panels. Thing is, in some games I can run crossfire all day long without problems. In others (deus ex as you noted) it has locked up in the exact same manner (hard lock, have to hold power button while audio loops). This has been an issue with every driver release, and I've tested dozens by this point. 12.8 is no better, Skyrim locked on me today after trying to enable crossfire.
Might be time to eBay these cards.
Might be time to eBay these cards.
I only ran a handful of games so I don't know if my old setup would have run some things all day long or not. Nothing I ran was like that. In Batman Arkham City, BF3, and ME3, it was hard lock city in 40 minutes or so each and every time.
Ok. I just bought a second 7970 and installed the new 12.8 drivers plus the new CAP. So far, I am not impressed as Witcher 2 randomly freezes and enabling Crossfire does no result into performance gain for FEAR 3.
WTF???
edit: Ok, I tried 12.7 and Witcher 2 still freezes.
WTF???
edit: Ok, I tried 12.7 and Witcher 2 still freezes.
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I gave up on Crossfire after I sold my 5870s to some bitcoin miners. I've tried it off and on with cards in each gen since X1900 XTs were out.
IMO if you want MGPU go nVidia. Yes, I've used SLi a good deal too. nVidia generally has better more prompt MGPU driver support. In addition, they have things like frame metering. SLi tends to feel more smooth in play. [H]ard has reported and commented on that more than once.
I've nothing bad to say about my single overclocked HD 7950. I did get occasional chop in Skyrim with it and I easily fixed that by limiting FPS with Afterburner.
IMO if you want MGPU go nVidia. Yes, I've used SLi a good deal too. nVidia generally has better more prompt MGPU driver support. In addition, they have things like frame metering. SLi tends to feel more smooth in play. [H]ard has reported and commented on that more than once.
I've nothing bad to say about my single overclocked HD 7950. I did get occasional chop in Skyrim with it and I easily fixed that by limiting FPS with Afterburner.
I had a great experience with the X1950XTX's in Crossfire and the same with X1950Pro's which I put in someone else's machine. They ran that setup for five years without issues and the guy knows next to nothing about computers. I've had OK experiences with some configurations since then, but only in limited exposure. I did have the Radeon HD 5970 which was a dual GPU card that worked well for me, but I didn't even try CrossfireX given all the problems it had with that setup.
In contrast, I've had dual GPU setups from NVIDIA from the 6800GT's to the GTX 680's in SLI, 3-Way SLI, Quad-SLI, etc. and for the most part each of these configurations was problem free. The only exception was the 9800GX2's which I couldn't wait to get off of. Microstutter abounded with those and their performance just wasn't there often times due to limited VRAM and limited memory bandwidth. The GTX 280 3-Way SLI setup served me faithfully aftwards for a long time. It replaced a problematic Radeon HD 4870x2 setup I never could make work. In fact I couldn't make a single card work right. It was a dual GPU card and I had problems with that by itself.
I have been with AMD for the three last generations and I have nothing to complain about the stability and performance of their single card solutions. My 7970, 6970 and 5870 were great performers.
Despite issues with Witcher 2 and FEAR3, Driver SF and Rage are so far performing well with Crossfire enabled.
Despite issues with Witcher 2 and FEAR3, Driver SF and Rage are so far performing well with Crossfire enabled.
The primary problems I usually ran into were;
AMD being late with proper profiles for new games, so I'd get negative scaling if I didn't disable Crossfire. Negative scaling is usually due to a missing driver profile.
Breaking working profiles in later drivers when they released them for new games. I saw this happen a few times with "Oblivion".
Texture flickering and microstutter. Sometimes they resolved that, and sometimes they didn't. "Age of Conan" had horrid shadow flickering with Crossfire enabled and when I would zone into indoor playing playing fields with AA active my FPS would drop to well below 20 and stay there. There was a level on "Crysis" where you could simply move the camera to a point and FPS would dive to below 20 no matter what was happening. With single card it was fine. I believe it was at the end of the "Harbor" level.
It some titles AMD's adaptive AA would make things transparent. I remember this happening in "Wow" "Everquest" and I believe "Crysis". I remember adaptive AA did something funky in "Crysis".
The above is not an exhaustive list, it's merely a few examples. Those are the ones I remembered quickly.
Sometimes the issues were resolved with later driver releases and usually by then I no longer played the title in question.
I'm not going to question folks experiences. I will take their word for it. Yes, sometimes Crossfire worked great for me and over time the annoyances would add up to make me abandon it.
SLi is not perfect either. My 7950 GX2 had a horrid stutter bug in some parts of "Tomb Raider: Legend". Honestly, my preferences based on personal experience go; single GPU, SLi then Crossfire.
The Tech Report has shown data that would support nVidia's SLi being "more smooth" in play and I have seen reviewers around here make that assertion after comparing Crossfire and SLi.
So currently if someone asks me for a recommendation I'm going to say; single strong GPU if it's enough, or SLi if that's not the case.
The bottom line is most games are developed for a single GPU and most consumers own that sort of setup. Most titles are targeted at the console. If MGPU works well in a title it's usually because the AMD or nVidia driver team put solid effort into making that so.
AMD being late with proper profiles for new games, so I'd get negative scaling if I didn't disable Crossfire. Negative scaling is usually due to a missing driver profile.
Breaking working profiles in later drivers when they released them for new games. I saw this happen a few times with "Oblivion".
Texture flickering and microstutter. Sometimes they resolved that, and sometimes they didn't. "Age of Conan" had horrid shadow flickering with Crossfire enabled and when I would zone into indoor playing playing fields with AA active my FPS would drop to well below 20 and stay there. There was a level on "Crysis" where you could simply move the camera to a point and FPS would dive to below 20 no matter what was happening. With single card it was fine. I believe it was at the end of the "Harbor" level.
It some titles AMD's adaptive AA would make things transparent. I remember this happening in "Wow" "Everquest" and I believe "Crysis". I remember adaptive AA did something funky in "Crysis".
The above is not an exhaustive list, it's merely a few examples. Those are the ones I remembered quickly.
Sometimes the issues were resolved with later driver releases and usually by then I no longer played the title in question.
I'm not going to question folks experiences. I will take their word for it. Yes, sometimes Crossfire worked great for me and over time the annoyances would add up to make me abandon it.
SLi is not perfect either. My 7950 GX2 had a horrid stutter bug in some parts of "Tomb Raider: Legend". Honestly, my preferences based on personal experience go; single GPU, SLi then Crossfire.
The Tech Report has shown data that would support nVidia's SLi being "more smooth" in play and I have seen reviewers around here make that assertion after comparing Crossfire and SLi.
So currently if someone asks me for a recommendation I'm going to say; single strong GPU if it's enough, or SLi if that's not the case.
The bottom line is most games are developed for a single GPU and most consumers own that sort of setup. Most titles are targeted at the console. If MGPU works well in a title it's usually because the AMD or nVidia driver team put solid effort into making that so.
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The 7950GX2 was a terrible setup. NVIDIA did not do well with the drivers on that card. Simple as that. TAnd during the Windows XP to Windows Vista switch, their Vista drivers were TERRIBLE. I recall 7950GX2 users ending up with the performance of a 7800GT because they couldn't leverage more than one GPU. Quad-SLI users were doubly screwed. It was months before this was ironed out and I believe many enthusiasts jumped ship to the 8800GTX by that point and rightfully so.
But I agree. Get the single most powerful GPU you can afford or are willing to buy. If that isn't enough get two.
As for the smoothness, except for BF3 I can confirm that was the case. Granted CrossfireX never worked on my 7970's for more than 40 minutes to an hour at a time. But during that time it felt OK. I certainly noticed more smoothness than a single card offered and the games were smoother with newer drivers. When I put a single GTX 680 in my rig while I waited for a second, (4GB availability wasn't as good as that of 2GB cards.) I immediately noticed that apples to apples the GTX 680 was smoother. In SLI I experienced the same thing.
That's not to say my experiences with a single Radeon HD 7970 weren't good or that it wasn't fast. That's not it at all. But the GTX 680's feel smoother even if the benchmarks tell you the 7970GHz Edition cards are faster.
You're not alone. And far form it. People with problems are always ten times more vocal/whining then people with perfectly working set-up. And probably that 99% of AMD users out there have perfectly working set-ups.
AMD sold millions of 6xxx and 7xxx cards. Millions.
Same here with RIVE + 4X Asus 7970 at 7680X1600. No problems at all. Can play all the games I have for hours without a single BSOD/freeze/stuttering, etc. I can't remember the last time I had a problem in the last 6 months honestly with that set-up.
I have a friend with the exact same set-up I have (but different brands of 7970), and it's working fine for him also (RIVE + 4X7970 Quad-Fire at 7680X1600).
So using D2CT doesn't have anything to do with it. My friends is using 4X 7970 from 4 different manufacturers and everything is working fine.
I am also having the same issue as you guys.
I will make some report like defcoms asked me to do.
I hope it get solved fast because not finding the problem is driving me crazy.
Refer to my thread at OCN: I tested everything already.
http://www.overclock.net/t/1295809/...70-ccc-12-8-12-x-crash-galore-what-to-do/0_30
I will make some report like defcoms asked me to do.
I hope it get solved fast because not finding the problem is driving me crazy.
Refer to my thread at OCN: I tested everything already.
http://www.overclock.net/t/1295809/...70-ccc-12-8-12-x-crash-galore-what-to-do/0_30
Well I solved the issue by switching to EVGA NVIDIA GTX 680 4GB cards in SLI. Flashing to the GHz Edition BIOS, disabling ULPS and upgrading to the Catalyst 12.7 driver did solve the issues outside of Eyefinity, but frankly not having Eyefinity support was a deal breaker for me.
Abraxas601
n00b
- Joined
- Nov 11, 2011
- Messages
- 33
Based on my own experiences (TriFire with 2x6950 and 1x6970) and others that I've read about regarding Crossfire and GW2, there is negative scaling occurring and you're better off sticking with one card at the moment. I'm also running the latest AMD drivers and Profiles (12.8 and 12.7 CAP 3).
I'm running at 2560x1600, maxed graphic settings, and getting 40 - 60 FPS
I'm running at 2560x1600, maxed graphic settings, and getting 40 - 60 FPS