EVGA GeForce GTX 660 SLi performance issues

[McGertz]

I just recently bought a second GTX 660 to run in SLi with my first one.

I havent really noticed any performance boost with it at all. I'm thinking of returning my second one.

I ran 3D surround with three monitors on my single 660 and it ran BF3 pretty good. I thought having a second one in SLi would make it run smoother, but it didnt. I notice it played a little worse. I had to plug two monitors into the first card, and my third monitor into the second. They are all using DVI - HDMI cables. DVI into the gfx cards and hdmi into the monitors.

Is running SLi and surround together a bad idea? should i return my second 660 and wait for a better single gfx card to run surround?

Im kind of annoyed with spending $200 extra bucks for no performance. I also bought a new PSU to support the second card, because my last one gave me a weird noise when i started up a game. I needed to replace the PSU anyways, so i'm fine with that.

So what am i really asking about? Is there any way to optimize the two 660's in SLi to get smoother performance?

I would think that this system shouldn't have any problems running games at decent graphics.

My current system:

Intel Core i7 3770k 3.5GHz
Gigabyte Z77X-UD5H Mobo
16GB Corsair Vengeance RAM
HX850w Corsair PSU
2xEVGA GTX 660 in SLi
3xAsus VN247 Displays at 60Hz (currently in Surround via Nvidia control panel)

 

[smorizio]

Make sure your mb bios is up to date. I would run gpu-z make sure both video cards are the same speed.memory size and type. If there not the sli won't work. If there the same cards check to see if the firmware the same one both cards.

 

[akshayghai29785]

check if SLI is enabled in nvidia control panel you should be getting performance above gtx 680 with the current 660 sli setup

 

[McGertz]

The Graphics cards are exactly the same, same speed, firmware, and i know SLi works and that i can span my displays with surround. It all works fine, but its just the performance in games. I need to turn down the graphics to normal/low to get smooth gameplay. I would have thought that using two decent GFX cards in SLI would make using Surround with 3 displays would be fine. I'll live with turning the textures down to low. BF3 still looks fine and Farcry3: BD still looks good in all of its neon'ness(not a word, i know).

I'll look for some game tweaks and gfx card OC features to get some more juice out of these babies.

Thanks for the help though.