Different brand crossfire

[qwazwaz]

I have an r9 290 w/ aftermarket cooler from gigabyte. It also came with a slight factory overclock. If I get another r9 290, does it need to be the same brand? I know that if the cards have different amount of VRAM, it will only use the smaller amount, but will the factory overclock complicate things?

 

[Rogue Leader]

It will work fine, however both cards will default to whichever card has a lower clock speed.

 

[barto]

No. For Crossfire to work, you pretty much just need the same GPU (the actual same core not the same card). So pretty much any 290 will work. When you link them, the faster one will clock down to the slower one.

Crossfire FAQ:
http://support.amd.com/en-us/kb-articles/Pages/AMDCrossFireFAQ.aspx