Crossfire slower than single card

[godamuss]

Hello,

ive got a crossfire problem.
2 6870 radeons
1080 sony bravia tv
24 gig ram
gigabyte GA-Z68AP-D3 motherboard
i5 2500 cpu
Thermal lake V3 VL8000 series tower case

So I guess i know that I got one 16x PCIe and one 4x PCIe slot. which is brutal. wish i knew b4 now.
this is making my games run choppy and slow. its major loss of performance is amazing. got the newest drivers and everything.
so what do i do , i just bought the second 6870 with christmas money, and am unsure if i can return it to tigerdirect now....
do i get a more capable motherboard ?
if so, how do i know the dimesions to fit my case ?

 

[godamuss]

http://hothardware.com/Reviews/Gigabyte-G1Sniper3-Motherboard-Review/

like this one, dont know if i can possibly fit it in my case.

 

[rolli59]

Your case being a mid tower fits any std ATX board or mATX. First on the performance did you before putting in the second card uninstall the first one in device manager, then shut down and mount the second one and reinstall the drivers with both cards in?

 

[godamuss]

cant say i did. what i did was plug it in and update the catalyst to the newest version. ill give it a try. it only seems to be affecting farcry 3, but i gotta say that i ran all other games at ulta settings before and after with no problems.

 

[rolli59]

Well it would be the correct way of going about it. FC3 is new and might have CF issues.

 

[godamuss]

ok. thx rolli, but a question or two if u dont mind.
1) should u unpulg the 2x6pins form the bottom card, restart, uninstall the top card (both in device manager), restart, plug the hdmi in the motherboard output, then let new hardware wizard run or install the CCC again ?
these are the correct steps yes ?
2) i read that a 4x PCIe slot will only cause a 10% loss of "utility", but read elsewhere that it only used 1gig p/s and the card itself is capable of way way way more. i suppse what im asking is that with my motherboard, what are the losses I should expect. i guess i dont even know if its PCIe 2 4x or 1 4x.

 

[rolli59]

I would remove the second card, uninstall in DM and then shut down and reinstall the second one. leave the monitor hooked to first card and then install CCC after boot up.
2 average is 10% but can be more depending on game.

 

[godamuss]

by remove , you mean take it out completly and just just unplug from the power supply ?
i just want to get this right in one try, im not really that thick.
you see the thing is also, i switched the card slots, because the shorter one doesnt fit because it is thicker and hits the sata "ports". the longer one is cut away at rthe end and goes over them. TMI right ?
anyways, just the bottom one right ?

 

[rolli59]

Out completely not to confuse anything. Yes the bottom one regardless of you switching them.

 

[godamuss]

be back in a half hour or so....

 

[godamuss]

well, my windows index is up from 6.0 to 7.6... good sign. i can run farcry 3 in ultra and it seems to run ok. until i get in a vehichle, which causes a very weird framerate. its not choppy , ut its not smooth, the water looks a little funny as well. strange that it a AMD enhanced game and it does not seem to work well with X-FIRE.. guess i wait for a patch. running it in DX11 is not possible though, there is a major bug, or flaw. hank you for the time rolli59 , it made things better than they were.