AMD Crossfire: Disabled

[Olteanu_1]

Hello dear friends,

I have a little problem trying to do a crossfire with two AMD R9 video cards but it seems that I've failed. I am looking in GPU-Z and it says that AMD Crossfire is: Disabled
R9 390X is mounted on first PCI_x16 slot and R9 285 is mounted on third slot (PCIE_X16/X8_3)

My build is:
ASUS ROG Crosshair V Formula
XFX Radeon R9 390X DD - 8GDDR5 512bits
Sapphire Radeon R9 285 - 2GDDR5 256bits
AMD FX-8370E (overclocked at 4.9Ghz)
Kingston 8GB DDR3 (overclocked at 1600Mhz)

I also have 2 PSU with an max. total output power of 980W. (Segotep550+EVGA430).

Any ideas with I'm not allowed to make them working as Crossfire?


Sincerely appreciated,
Alex O.

 

[IDProG]

Have you connected them with a CrossFireX bridge?

 

[krells]

In order for crossfire to work you need the same gpu or at least a chip in the same family. The 390x and 285 cannot work together in crossfire.

 

[IDProG]

Oh, yes, I forgot to take a look at the GPUs.

 

[Dunlop0078]

Have you connected them with a CrossFireX bridge?

Oh, yes, I forgot to take a look at the GPUs.

No bridge is required for crossfire. Yes you cant corssfire a 285 and 390. Even if you could im not sure I would personally be comfortable with how you are powering them, using two quite low quality psu's.

 

[Olteanu_1]

So, if I understand correctly I will need same GPU chip (Hawaii based) ?

 

[Supernova1138]

So, if I understand correctly I will need same GPU chip (Hawaii based) ?

Correct, you can only do Crossfire with another 390x, a 390, or the 290x or 290 which are basically the same cards with less VRAM and slightly lower clockspeeds. It's also not a great idea to run two power supplies in your system to get enough juice for your cards, you really should look into a high quality 800+ Watt unit, especially if you want to Crossfire high end AMD card which are pretty power hungry.