CrossFire with 7870 GHz edition with R9 270X on Battlefield 3

[dropwater]

I bought R9 270x since I had HD 7870 already, so I tried to crossfire with it and set 270x as the primary card.

everything work fine and crossfire enabled, I am able to see 99 % activity on 7870 while Battlefield 3 is running.

but here comes the problem, I tried to set all to ultra but fps drop down to around 10~20
if I set to high, everything work pretty well

Here is my system
AMD FX 8350 4.2 GHz
Gigabyte 990FXA-UD3
12 GB ram
HIS R9 270X
Sapphire HD 7870 GHz edition
Window 8.1
Driver is 13.11 which is the newest , I even did a driver sweep before install the new one

Resolution is 5760 x 1080 ( I have eyeinfinity enabled )

I didnt try ultra on 1920 x 1080, but I saw some people playing ultra on 5760 x 1080 with CF 7870 without a problem. I wonder why I cant turn on ultra setting.

I can still return my 270x for another card like GTX 770, what do you guys suggest for me.\

Sorry for poor english and grammer

 

[SEC9-HavokMR2]

You can't crossfire a Nvidia and AMD card. The video settings in BF are almost unnoticeable between Medium through Ultra settings. Running low on Lighting Effects will save you almost 10fps.

 

[bhuvanesh123]

Buy 770 gtx, the new drivers for nvidia is awesome, please return 270x and get gtx 770. drivers in AMD just suck. or sell everything, and wait for maxwell.... its not too long away.

 

[haznix]

It's good to know you were able to successfully crossfire AMD R9 270X with HD7870. Did you check with AMD if the two have any operational issues? Did you match the clocks on the cards (i.e. OC the 7870)?

 

[haznix]

You can't crossfire a Nvidia and AMD card. The video settings in BF are almost unnoticeable between Medium through Ultra settings. Running low on Lighting Effects will save you almost 10fps.

Both his cards are AMD.