SLI 680s - different clock speed?

[BaDBoY_uK]

Hi all

Spec
2 x EVGA 680 4GB FTW versions
X79 3930k
ASUS RIVE

I have noticed that during gaming, the clock speeds and power percentages of my two cards are different. Weird! The slots being used are 1 and 4, i.e. both x16

Any ideas? I use MSIAB/EVGA Precision to monitor and display sensors

 

[setter]

Slightly similair qwery in this post here regarding running gtx 670's in sli and overclocking.

http://forums.overclockers.co.uk/showthread.php?t=18468951

 

[Rusty0611]

The 600 series boost differently out the box to each other depending on the silicon quality.

 

[Gregster]

I have 2 MSI Lightnings and in AB, I have the box ticked "Synchronize settings for similar graphics cards". Both my lightnings run at the same speed with this box ticked. I did have 1 EVGA 680 and 1 Lightning before and they both ran at different speeds. I would say it is the chip lottery playing a part here.

 

[BaDBoY_uK]

I see. Thanks all
It doesn't affect gaming, just weird.

 

[OptimaLnrg]

The clock speeds are adjusted constantly by the driver.

For example, if I set a 120fps limit, running the easier parts of heaven pushes one card at max, while the other clocks down slightly (1080p)

 

[BaDBoY_uK]

Now that I have three cards they are all over the place. I notice that the higher speed card uses less GPU than the other two, which makes sense? It is worth breaking the link between them in MSI AB and trying to achieve the same clock speeds?

I also need to remove card 2 and make it card 1 as that is the most "powerful"

 

[Kaapstad]

Now that I have three cards they are all over the place. I notice that the higher speed card uses less GPU than the other two, which makes sense? It is worth breaking the link between them in MSI AB and trying to achieve the same clock speeds?

I also need to remove card 2 and make it card 1 as that is the most "powerful"

With 2 GTX 690s things get even more interesting 3 sometime 4 different boost speeds, its quite normal though.

Moving the most powerful card to slot 1 is a good move as this helps carry the weaker cards.

 

[BaDBoY_uK]

Moving the most powerful card to slot 1 is a good move as this helps carry the weaker cards.

I'll do that Kaapstad, cheers.