SLI Issues

[drums101]

Ok So I have 2 bfg gtx 285s in SLI and an intel dual core cpu at 4.1ghz. I run games at the right fps when not running SLI but when I enable SLI I get lower fps. I know that both cards have plenty of power and I have tested this on two different motherboards. Even if the cpu is a bottleneck to the cards I would still see a jump in fps when going from one card to two not a loss in performance. But the thing that really gets me is that my vantage score is right on target its right around 23k. The p score. the two games that I test on are Call of duty world at war and Far cry 2. Any suggestions on what to do? I would appreciate any help. I have tested each card individually and they both work fine by themselves. Thanks.

 

[OvrClkr]

What brand is your 780i motherboard?

 

[knotknut]

What power supply are you using?

http://www.pcpower.com/Power_Supply_Selector.html

http://www.corsair.com/

here a couple of PSU guides from people who Know.

 

[OvrClkr]

I dont think uderpowering a GPU will give you lower frames when in SLI, I think its a bios setting he needs to change. I have an Asrock AMD board that is similar to some ASUS boards that have a switch card, meaning I have to switch the card to the opposite position if I want to run Sli, if not it either runs alot slower or I get an error....

Thats why I am asking him what kind of 780i (brand) does he have... but it looks like he has not been online for a while.....ohh well...

 

[drums101]

Oh sorry i have been busy trying to fix this and I have an EVGA 780i board and I have run 9800gtx sli on it before no problems as for the psu its a 750 watt pcp&c it does the job fine thanks for the suggestions

 

[OvrClkr]

Yea the PSU is more than enough for DUAL 9800GTX's, have you tried looking in the BIOS for an SLI setting?

 

[drums101]

well im running gtx 285s now so it does take more power but the green leds on the cards are always green under load so thats all good and yea there isnt anything about SLI in the bios except for the SLI ready ram

 

[OvrClkr]

Ok, im at work at the moment and kinda swamped.... once I get home if you have not found the solution, I will look into this further.... we will fix this issue today....

 

[drums101]

thanks man i apprecitate it

 

[OvrClkr]

Np, one last thing before I leave work.... What model of 285's are you using...since I have to call EVGA anyway when I get home I can use this info to kill 2 birds with 1 stone....

 

[drums101]

I have two BFG gtx 285 OCX

 

[megamanx00]

Well the first thing to check is to make sure that your cards are running with the correct number of PCI-E lanes and that they are indeed running in SLI. Run GPU-Z to check their status. Since SLI adds CPU overhead it can cause a drop in FPS, especially if your CPU is the bottleneck. Before blaming the CPU though I would check to see if it's a driver problem. Uninstall your drivers and use drive cleaner pro. From there install current drivers and see if the situation improves.

 

[drums101]

yeap i have done everything with the drivers I have tried this one win 7 64 vista 64 xp 32 and tinyxp and I get the same exact issue. I know for a fact that SLI has been on b/c of gpuz like you said. I have even tried different CPUs a quad core at 3.4 and then a dual core at 4.1 with same results i have tried different boards a evga 780i and a xfx 680i lt to no avail the only thing that I think it is is possibly the cards themselves but then i dont get why 3dmark vantage gave me a good score of 23k with sli while games lose fps with sli its crazy!!!

 

[OvrClkr]

yeap i have done everything with the drivers I have tried this one win 7 64 vista 64 xp 32 and tinyxp and I get the same exact issue. I know for a fact that SLI has been on b/c of gpuz like you said. I have even tried different CPUs a quad core at 3.4 and then a dual core at 4.1 with same results i have tried different boards a evga 780i and a xfx 680i lt to no avail the only thing that I think it is is possibly the cards themselves but then i dont get why 3dmark vantage gave me a good score of 23k with sli while games lose fps with sli its crazy!!!

Im on hold with EVGA right now....

 

[drums101]

Im on hold with EVGA right now....

how did it go you get any information that helped you? or did they blow smoke up your a$$? lol

 

[drums101]

Im on hold with EVGA right now....

how did it go you get any information that helped you? or did they blow smoke up your a$$? lol

 

[drums101]

wow my bad on the double post idk how I did that

 

[OvrClkr]

how did it go you get any information that helped you? or did they blow smoke up your a$$? lol

sorry for the delay....and yes smoke up my @ss... i called both BFG and EVGA and accomplished nothing. 45 min wait then put on hold and then the dude hung up (BFG), 25 min wait then put on hold and then he had no idea of how to even answer the easiest questions.....

 

[hundredislandsboy]

Since your 3DMark Vantage scores basically confirms functionality with hardware and driver, I would look at the game publlisher site for SLi issues and perhaps a patch.

BTW, what game/s is it, resolution, AA settings?

 

[swifty_morgan]

go into the control panel and disable physics. While you're there check and see that vsync is off. What happens ?...... If you're not running windows7 go back and find slightly older drivers..... ones that don't say anything about being Windows7 capable.

 

[Mousemonkey]

go into the control panel and disable physics. While you're there check and see that vsync is off. What happens ?...... If you're not running windows7 go back and find slightly older drivers..... ones that don't say anything about being Windows7 capable.

What a stupid suggestion, just what a noob would suggest!

 

[swifty_morgan]

What a stupid suggestion, just what a noob would suggest!

Baby steps.......... and up yours dipshit.

 

[drums101]

I know vsync is off and I will try the older drivers the games that are giving me issues that I have tested are Call of duty world at war and far cry 2. 1920x1200 4x AA maxed out. I am pretty sure every game is giving me issue tho.

 

[swifty_morgan]

I looked up the power supply. 60amps. A single GTX260 requires 36 I think it is. I run an 850 in the 70amp neighborhood. No problems. I tried running them ( sli ) on a 52amp psu.., not so sweet.

 

[Mousemonkey]

Baby steps.......... and up yours dipshit.

What a mature and measured response, a shining example of how much knowledge you don't have.