Radeon 6970 and 6950 Crossfire worse Performance Than Single 6970

judahg460

Commendable
Aug 3, 2018
66
0
1,640
Hi, I got a Radeon 6970 and 6950 to run them in crossfire. In unengine valley, the 6970 got an average of 67 fps, but the crossfire got 59. I have a crossfire compliant mobo, so i don't understand why it is not giving me a performance boost. Please help as soon as possible, because I need a case for my pc, and if i can't get a performance boost ill just sell it on ebay and buy a case. Here are my full specs

FX 8150 CPU

16 gb Corsair vengeance RAM

Antec kuhler h2o 620 water cooler

2 hdd (one 70 gb and one 1tb)

mobo= 990 FXA-GD80
 
Solution
Yes. Core clock and memory clock need to be the same.
Honestly, you should go ahead and sell them. The strongest single card solution you can afford > CF/SLI any day of the week.
The benefits pale in comparison to the downsides.

So you got the temps down on the 6970 by way of modding, but what about the 6950? Are you instead using the 6970's cooler on it? What are the temps after that?

judahg460

Commendable
Aug 3, 2018
66
0
1,640
I have a 750w EVGA power suppy. I am using 2 molex to pcie power adapters to power the second card. Ill have to check my idle temps but on full load the 6970 runs at 180 feriheight and the 6950 runs idle at 160 ferinheight. The difference in temps i think is because of the cooler. I modified the 6950 cooler to fit on the 6970 and the 6970 ran 20 degrees cooler in ferinheight. Would the clock speeds on the cards cause an issue? I never set the clock speeds the same when I ran them together.
 

Phaaze88

Titan
Ambassador
Yes. Core clock and memory clock need to be the same.
Honestly, you should go ahead and sell them. The strongest single card solution you can afford > CF/SLI any day of the week.
The benefits pale in comparison to the downsides.

So you got the temps down on the 6970 by way of modding, but what about the 6950? Are you instead using the 6970's cooler on it? What are the temps after that?
 
Solution

judahg460

Commendable
Aug 3, 2018
66
0
1,640
Well right now I am only using a single card because of the crossfire issue, thats why I have the 6950 cooler on it. So right now the 6950 is sitting next to me with no cooler on it. I am gonna start the cards up in CF and then match their clock speeds, and test them both before(Single 6970) and after(Both cards in crossfire) in unengine valley and EA Battle Front. Then ill give you the difference. If the increase is only something like 5 fps then I am gonna sell the 6950 and get a case for my pc, because I am currently running it on a motherboard box.
 

judahg460

Commendable
Aug 3, 2018
66
0
1,640
Well, The 6970 got an average of 107 fps in battlefront and 66 in unengine valley. The crossfire got 70 in unengine valley and battlefront would crash and when i finally got to playing it glitched out and i couldnt play it. I want to get it to work with battlefront but i dont know what to do. I will probably end up selling it anyway.