Mismatching GPUs and OCing

[Bartacus]

Is anyone else around here dumb enough to be running mismatched GPUs in Crossfire and OCing them? I'm running a pair of Sapphire 7950's, one is a 7950 reference PCB, the other based on the 7970 PCB. Both cards draw different voltages, and I suspect one of them is a crappy overclocker. Trying to OC these things as a pair restricts me to 1050mhz core (which I guess isn't *too* bad).

Anyone else in that situation? Do you set the OC settings as a pair, or can you do that individually without sacrificing stability?

 

[Thelosouvlakia]

Well you can't have everything... AMD has that thing that you can CFX different GPUs but that's it.
What are you using to do the OCing btw?

 

[Bartacus]

MSI Afterburner for now. I've tried everything else, but that seems to work best.

 

[NeverBackDown]

what were stock clocks?

 

[Bartacus]

Stock is 925 core, 1250 memory. I'm currently running 1050/1400. I should say that I am happy with these clocks, and I do get a nice performance boost from em (~300-350pts more in Heaven at 1080p extreme). I was just wondering if could OC the cards individually with mixed clock speeds, assuming one OCs better than the other. It's probably not worth the effort, but I'm bored and I can't afford new GPUs.

 

[Davva2004]

I'm pretty certain the clock speeds need to match, so you'll be limited to the speed of the slowest card. I'm sure someone with more knowledge will be along to either confirm what I've said, or call me a knob.

 

[Bartacus]

You're probably right. I just wondered if anyone else tried to run em separately. I'm sure even if it did work, it probably wouldn't be worth the headache.

 

[Master&Puppet]

There's no point setting them to different setting for gaming anyway. At best it will have no effect on performance because the faster one will wait for the slow one or worse it will increase frame stutter.

 

[tinytomlogan]

You can get that even with matched cards

Silicone lottery

 

[Bartacus]

I'll leave well enough alone until I can afford an upgrade. Thanks for the input gents.

 

[iBeInspire]

Tbh in crossfire if one was to be at a higher clock than the other, your perceived framerate would actually be worse because of the frametime difference.