Crossfire Card Mixing

[jonathan_phang]

Hi all,

recently managed to get pick up a second hand Gigabyte 7970 Windforce 3x to replace my now-starting-to-age 5850 crossfire setup. Now, my plan was to have one GPU for a while, then pick up a second when subsequent generations drive the price down (Like I did with my 5850s).

However, I've now found that the Windforce doesn't overclock that much (on the vcore). Not a massive deal for now, as its running everything very well. However, if I get a second 7970 down the road, and that one overclocks well, what implications does that have for crossfire performance?

Back when I started 5850 cf, if one card was faster, then it would effectively only run as fast as the slower card. I dont think thats the case now, but can anyone give clarity on this? If I got a non-voltage locked 7970 and overclocked it well (Like to 1200 on the core), would I get any benefit from that OC? Or would it still run as fast as my current, not very overclockable, card due to the way cf works?

Would just like to know so that when the time comes, I can look to secure ones that dont necessarily have to be OC friendly.

Thanks

PS. Such a shame about the card, the cooler is so wonderful, shame its going to waste. If it didnt perform so well at 1920x1200 I would get rid of it. Oh well, whats done is done.

[flearider]

think it's the same as befor .. as the cards still have to sync .. but why get rid of the 5850 cf .. that would give you good results for a few more yrs yet ..
and with cf it should be almost as good as a 7970 .. in real world terms ..