ATTENTION ALL WHO ARE HAVING ISSUES WITH SWTOR AND BF3 SLI PERFORMANCE ISSUES!
 
Are you getting only 50% usage from each of your SLI'd cards? Are u getting 100% usage from each of your SLI'd cards but performance is dismally low? DOWNLOAD THIS! It solved all my problems in every game that was suffering from horrible performance even though SLI was "working" in them!
 
http://www.evga.com/artic...fault.asp?d=1&b=32
 
The Evga SLI Enhancement patch works wonders! I SLI'd my 1792mb GTX 275's and with default settings, a bunch of tweaks involving Nvidia Control Panel, then further tweaking using Nvidia Inspector, I couldnt get SLI working properly in BF3, SWTOR, Assassin's Creed Brotherhood, and Batman Arkham City. With 1 card, in almost all these games with High to Ultra (Maxed out) settings, I was getting anywhere from 35-50ish FPS. When I added my second card, I was still getting 99% GPU usage on both cards... but my performance was dropping down to 11-18fps to around 26-36fps. BF3 went from 1 card giving me 36fps avg to 18 fps avg with 2 cards. SWTOR went from giving me 70fps indoors/46fps outdoors avg on 1 card to 60 fps indoors/24 fps outdoors and pretty much the same or close enough drop in fps numbers for the other two titles as well.. 
 
WELL!!!!...... After the SLI Enhancement patch by EVGA... 100fps indoors/50-60 fps outdoors in SWTOR, 70-100 fps w/o AA in BF3, 51-61fps with AA v-sync enabled, up to 70 fps with AA enabled and no v-sync. Brothrhood is smooth as butter and Batman was the most optimized between the 4 to begin with... With the patch and settings beefed up even more in terms of AA (16xQ)... BUTTER! BUTTER, people lol..
 
Download the patch and be glad u didnt buy XFX or Radeon lol.. (I love Radeons and respect XFX very much btw)... EVGA forevga!
 
 
EDIT: Batman numbers are up: from 17fps avg to 42fps avg with this enhancement!
 

Link to article describing it.
 
Looks like it's just a set of custom SLI profiles (that is, the things you can configure in the drivers).
 
So if:
A) You are running the latest drivers that include SLI profiles for your games...
or
B) You've already configured your own SLI profile for the game...
 
...then this isn't going to do anything for you.
 
But it does make a nice drop-in fix for those who don't want to tinker around in their nVidia control panel, or who are running older drivers.

I'm running the latest March 296 drivers... and before those drivers I ran a couple of 295s all the way to 285 drivers... no cigar, didnt help. I also made custom SLI profiles using Nvidia Inspector as I stated in my OP. Didnt help. This custom set by EVGA did everything in one fell swoop. It wouldnt hurt anyone having problems persisting after trying everything to try this solution out. I've seen sooo many posts about people begging for proper SLI support in SWTOR.. this is by far the only thing that has had a DRAMATIC change in postive FPS numbers (especially outside!) for it. What game(s) are you having SLI issues in?

can i run two ati cards on my 790i ultra motherboard?

No cause its not crossfire capable, only sli