6950 xfire scaing and BF3

[p1987]

I've just borrowed and installed an additional 6950 to test the scaling. Firsty, I've used 3d mark 11 to test the score agains a single 6950;

Single 6950: approx 4,400

Xfire 6950: approx 7,800

I have tested the single 6950 an xfire 6950's in Battlefild 3. I've noticed thes not much performance gain. it sems quite sluggish an i get more frequent drops in fps. I expected alot more performance for the price i'm going to possibly pay for the card. Is there any particular reason for this 'lack of performance in xfire?'

In addition, im using a Dell 19" wide screen monitor at max resolution of 1440x900.

system specs bellow,

Thanks.

 

[marsey99]

1156 is pci e limited, could this be the reason?

 

[MOOGLEYS]

Have you overclocked your CPU ? BF3 is a poorly coded game and does not benefit very well from crossfire.

 

[Robbss]

I'm running BF3 maxed out in 1920x1080 on my single 6950, pretty sure its either your memory or CPU bottlenecking, how much memory have you got?

 

[p1987]

Correct, 1156 is limited to x8 - x8 pci express lanes, however there are no cards out to date that will use the full bandwidth of this.

No, my CPU is not overclocked.

I've got 8gb of Corsair Red Vengence memory.

 

[marsey99]

i wasnt sure what it broke the lanes down to, x8 x8 wont hinder it too much.

i would try an overclock on the cpu and see how it scales with and without xfire as it is another idea, your cpu culd be bogged down at stock speeds feeding both cards and more ghz would help if that is the case.

 

[leejc73]

Battlefield 3 hates Crossfire. Don't quote me on this but there was a set of catalyst configs that actually disabled crossfire when running BF3 because actually getting the game to start up is about 10% successful in crossfire, I saw this with my 2 DCII's as I was very surprised it started up at all, when I exited I checked CCC and it had disabled Crossfire.

Which issue of CCC are you using?

Don't attempt any overclock because it will just crash at the load screen, there is a thread somewhere on another forum about Battlefield 3 and getting it to work with crossfire and it was about 40 pages long last time I looked. I got rid of the 6950's and stuck a single 7970 in there and average 88fps in BF3 now on ultra.

 

[MaXiMiZe]

Would you guys say that BF3 likes sli more than xfire?

 

[p1987]

Thanks for the information leejc73.

I have overclocked the cards (no bios flash as of yet) and only once i've ever encountered an issue with bf3 getting stuck at the [] loading screen, but I think this was due to the server shutting down as i couldnt see the same server after that.

After configuring CCC 12.1 to set its own config for crossfire for BF3 i've noticed about a 25 fps increase in-game. Still though, when i'm on rooftops looking down at a battle, even with crossfire enabled. i drop down to 45fps and the slowdown begins from there.

I will however, take a look to see if BF3 has disabled xfire while ingame.

I've even clocked my processor to 3.5 with no fps increase.

I'm in abit of a rip-off situation, you pay and additional £200 for an xfire setup and don't get when you've payed for, very frustrating.

I may just buy the additional 6950 from my mate for £130 and sell them both off now and get a 7970.

Less a**ing about with crossfire.

In addition; Would I benefit more if I had a larger screen?

 

[Robbss]

I honestly cant see how it will give you so bad framerates, my single 6950 gives me 90 FPS in 1440x900.

my friend has a CrossFireX setup with 2 6950s and he gets 55 - 60ish FPS with 3 screens at maximum 5760x1080..

 

[kickbackman]

had my xfire 6950's for about 24 hours and so far i am very happy with them. in some games i have noticed that the fps dont go up by much but at the same time the fps drop is no where near as bad. as an example settlers 7. at max setting i get 40fps with one card and that can drop to 18-19fps. now with 2 cards i get 42-43fps but it never drops below 32.

so i am very happy with the 6950's