Two 7970s in crossfire slower than one alone?

G

GaryR

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Nov 18, 2013
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I've seen and read about this issue but have not seen a solution anywhere. I have two Gigabyte GV-R797OC-3GD cards (added #2 this week), linked in the following system:

Antec Full Tower/New Rosewill RBR1000-M 1000W PSU
Gigabyte GA-P67X-UD3-B3
Intel i7 Sandy Bridge at 3.8gz
8Gb Crucial
64 GB SSD/ 2TB 7200
2-Gigabyte GV-R797OC-3GD in Crossfire.

Both cards show up fine in GPU-Z and CCC, Crossfire mode enabled, nothing overclocked. One odd thing is the power meter in CCC Overdive, it shows 0 for Card #2 and all the Ghz clocks are at 0 also. Is that normal? In the three games I currently mess about with - BF3, ARMA2 , And ARMA3. Issue is the frame rates are no better, and at some points actually seem worse with Crossfire enabled! I bought the second card to increase FR and eye candy, not decrease it!

Thank you for any help..
 
The 2nd card showing 0 is ulps or ultra low power state. Which basically turns the 2nd card off when not under load (fans spinning but thats it). I would try turning this off. Usually if people have problems with crossfire it is because of ulps. Bf3 you wont see much gains with a stock sandybridge as the game is very cpu intense. Taking it up to around 4.5-4.6 will help a lot. Also if you werent using 4xmsaa with your single card you wont see much gain with 2 cards as without 4xmsaa the load will be pretty even between your cpu and gpu. With 4xmsaa there is a lot more load on gpu. Therefore more gains with 2 cards. Overclocking that cpu is going to be pretty necessary tho. I cant speak for the arma games.
 
When you get performance with Crossfire that is less than a single card that is likely because a proper profile for the app in question isn't present in the driver. BF3 should certainly work well with Crossfire. I've no experience with ARMA 2 or 3.

I've had good results with Cat 13.11 Beta 8. I've not tested the latest driver.

http://www.techpowerup.com/downloads/2295/amd-catalyst-13-11-beta-8/
 
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Thanks guys. I updated the BIOS on both my motherboard and the video cards to the latest last night, then grabbed the latest Cat driver set. Seems about the same but i'm going to try some other games as it could just be the ARMA series that doesn't like crossfire. As far as ULPS, where would I begin looking for that setting? MB BIOS?
 
I know when I tick the checkbox for forcing crossfire if there is no associated profile my framerate goes to shit in MWO, because PGI don't understand how to program.
 
Disabling ulps won't change the outcome. All it will do is make the card active for you at idle. If your cards are scoring lower together then they are apart it seems driver related to me. Did you test both cards alone? And did you do anything to drivers recently? People have been having these issues with the new 290 drivers also. Of you are on the new beta drivers I would auggest findng the last stable version of drivers before the 200 series released drivers.

Edit: and as the guy stated above, there may not be a xfire profile for that game. Try running a benchmark to find out of its running correctly also
 
k thanks, i'll run Heaven tonight and post the results.. Downloaded it and ran for a while on my office desktop, was getting 2FPS and I finally pulled the plug after 10 minutes... Does it give Benchmark numbers at the end of its run?
 
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try defaulting all you catalyst settings - seems you may have something enabled. def should be more than 2fps :)
 
KaptainKhaos said:
try defaulting all you catalyst settings - seems you may have something enabled. def should be more than 2fps :)
Click to expand...

That was on my office machine... Ran Heaven on my machine and got:

Unigine Heaven Benchmark 4.0
FPS: 124.4
Score: 3133
Min FPS: 30.3
Max FPS: 212.0
System Platform: Windows NT 6.2 (build 9200) 64bit
CPU model: Intel(R) Core(TM) i7-2600K CPU @ 3.40GHz (3409MHz) x4
GPU model: AMD Radeon HD 7900 Series 13.152.1.8000 (3072MB) x2
Settings
Render: Direct3D11
Mode: 1920x1080 4xAA fullscreen
Preset Custom Quality High
Tessellation: Disabled

Ran 3DMark,
Icestorm scored 135246
CloudGate scored 23248
Firestrike scored 11470 - says it is better than 96% of all results
 
GaryR said:
I've seen and read about this issue but have not seen a solution anywhere. I have two Gigabyte GV-R797OC-3GD cards (added #2 this week), linked in the following system:

Antec Full Tower/New Rosewill RBR1000-M 1000W PSU
Gigabyte GA-P67X-UD3-B3
Intel i7 Sandy Bridge at 3.8gz
8Gb Crucial
64 GB SSD/ 2TB 7200
2-Gigabyte GV-R797OC-3GD in Crossfire.

Both cards show up fine in GPU-Z and CCC, Crossfire mode enabled, nothing overclocked. One odd thing is the power meter in CCC Overdive, it shows 0 for Card #2 and all the Ghz clocks are at 0 also. Is that normal? In the three games I currently mess about with - BF3, ARMA2 , And ARMA3. Issue is the frame rates are no better, and at some points actually seem worse with Crossfire enabled! I bought the second card to increase FR and eye candy, not decrease it!

Thank you for any help..
Click to expand...

Welcome to AMD's shitty CrossfireX support. You are almost at the same level of hell I was in with the 7970's. The second card usually made things worse and when it didn't the system would hard lock in about 30 minutes or less. Frame pacing also wasn't in the drivers and thus even when the benchmarks were good the things didn't "feel" smooth.

A single HD 7970 is a great card and I had zero issues, though the lack of frame pacing in the drivers hurt in some games. I think the hardware is better in some ways than NVIDIA's at the time, but in a lot of the areas that matter such as actually playing games instead of benching, and with regard to multi-GPU support the 7970's are some of the worst cards I've ever seen since the debut of the 3D accelerator. Why? AMD crippled them with some of the worst software support they've ever had since the Radeon brand was introduced.

Updating the BIOS ROMs of the cards can fix the 0 readings in CCC. I had to use the GHz Edition reference BIOS on mine to do that. As for the crappy performance in CrossfireX, the drivers shouldn't be doing that anymore as they supposedly fixed that in a driver update 2 months after I got rid of mine.
 
^^ Ya' I use to dislike Crossfire myself. Cat 13.11 Beta 8 completely changed my mind though.

After my Crosshair V died I tossed my 7950 in with my 7970 in my other computer and gave Crossfire
another chance for the hell of it since the card wasn't being used. That computer has a 3570K @ 4.6GHz.

I've both cards doing 1150|1635 currently.

So far, I've no complaints.
 
After BIOS flashing and Catalyst updates I was able to achieve successful results in CrossfireX with two HD 7970's at 2560x1600 on one monitor. Going past that I had lock up issues and problems which were denied by AMD until notes showing a fix for this mysteriously appeared about two months later in a driver update.

They still didn't have frame pacing in their drivers so even when they worked they never felt smooth to me. Now, the R290X impresses me in both a performance and for the value. The total redesign of CrossfireX doesn't surprise me either as my research indicated that CrossfireX's bridges have severe bandwidth limitations which just can't be overcome in software. Hence the need to redesign it for supporting 4k+ resolutions and multiple monitors.
 
I think the issue is lack of profiles for some games as BF3 flies at over 125FPS in full Ultra resolution now. Forcing Crossfire in games that don't support it may be an issue also (slower FR than 1 card) so i'm going to try it with that box unticked next. I popped in ARMA3 online just before bed, still saw only around 30 FPS but seemed quite smooth, had it self-adjust res and it was on the highest settings..
 
I'd love to know how you all are getting over 4K out of your CPUs, mine isn't perfectly stable over 3.8 but I haven't messed with voltages and other settings I know little to nothing about.. I'm thinking of a new GIGABYTE GA-990FXA-UD7 mobo and the new AMD FX-9590 Vishera 4.7GHz Socket AM3+ 220W Eight-Core Desktop Processor - Black Edition FD9590FHHKWOX with Liquid Cooling Kit, wonder how that would compare?
 
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GaryR said:
I'd love to know how you all are getting over 4K out of your CPUs, mine isn't perfectly stable over 3.8 but I haven't messed with voltages and other settings I know little to nothing about.. I'm thinking of a new Gigabyte mobo and the new AMD running at 5K, wonder how that would compare?
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It's pretty easy to get 4.4GHz and better out of a Core i7 2600K. 4.4GHz-4.6GHz+ is actually pretty easy, but you do have to adjust your CPU voltage, CPU PLL overvoltage, CPU PLL voltage usually at the very least.
 
Dan - Is there a walk though somewhere for setting, like on Overclockers?
 
veedubfreak said:
Watercooling helps. My 3750k gets unstable after 4.5ghz regardless of cooling.
Click to expand...

The 2500K and 2600K's overclocked more easily than the 3750K and 3770K's did. And 4.5GHz on air isn't all that bad.

GaryR said:
Dan - Is there a walk though somewhere for setting, like on Overclockers?
Click to expand...

We've never written one. Not sure if anyone else has. I know ASUS has put out guides for their ROG boards and the information provided works on their other motherboards and even other manufacturers boards in a general way.

What you need to know mainly is this: For 2500K/2600K's they need CPU PLL Overvoltage set to Enabled. CPU PLL voltage needs to be about 1.85v-1.95v. There is some give and take on some boards, but I've found this to be almost universally true. CPU voltage needs to be around 1.4-1.5v on those if I recall correctly. The fastest speeds I achieved on a 2500K were about 5GHz. http://www.hardocp.com/article/2011/11/10/asus_p8z68v_motherboard_review/6#.Uo071meA1t4 More advanced tuning includes adjustment of the power phase control (usually set to 75% or 2/3rds maximum for thermal balance and good power delivery.) You can also adjust the PWM frequency response where applicable to nearly the highest settings but you usually won't need that unless your really on the edge of the CPU / board capabilities.

Similar techniques work on 3570K and 3770K CPUs. PLL voltage is usually a bit less at 1.90v or lower and CPU voltage drops into the 1.4x range. Haswell is a slightly different beast and in many ways even easier to work with. Really though overclocking Intel CPUs hasn't required a great deal of tuning since the X38/X48/P35/P45 days. Seriously, 3-5 settings are all you normally need to adjust most of the time.
 
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Just to report, with the "Enable CrossfireX for applications with no profile" unchecked and everything updated i'm at 50+FPS in ARMAII and in ARMAIII with a couple tweaks per the thread, most settings on Ultra, here on it am at close to 60FPS also! Weird in ARMAIII, untill I disabled VSYNC it was locked at 30FPS on my 60hz Samsung..

Dan - thanks for the tips on the OC, i'll look into it.
 
Read the great walk throughs here - http://www.overclock.net/t/910467/the-ultimate-sandy-bridge-oc-guide-p67a-ud7-performance-review and here - http://www.overclockers.com/3-step-guide-overclock-core-i3-i5-i7/ , ran at 42X for a while but CPU cooler is stock and it got up to 78C so I dropped it back down to 36X until I get more toys. Ordered a Noctua NH-D14 120mm & 140mm SSO CPU Cooler and some Arctic 5 compound from Newegg, will see what I get next week. CPU voltage was auto set at 1.34, back down to 1.28 now..
 
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