I am Sooo Confused!

I just don't understand what's happening.

Here's what I put together

a8n32 sli deluxe
amd 64 3800+
2 x ocz plat 3200
2 x bfg 7800 GT's

So I tried out one card first to see what it would do. I didn't do any benchmarking yet, I just went straight to trying Call of Duty 2 and I looked at the FPS. No Problems. Good FPS.. Quick load.

Then, i decided to run another 7800 .. Both are identical.
I have them set up in SLI - set to 16x and the rendering mode is set to SLI antialiasing.

So i ran the game again. This time it took 3 times longer to load the maps and the game. AND the FPS dropped significantly. I changed it to single GPU mode to see if it would do anything. It didn't.

Is it possible that one of the cards is Kaput? How do I check to make sure the cards are running ok individually? Other then running 3dmark03 and 05 and getting the bench marks, is there any other way to see if a card is damaged and needs to be RMA'd

Thanx in advance for the help

Hey Ya, I didn't mention that in the original post, I had already tried both cards individually on their own and the results were both the same. So the problem happens when it is in SLI mode.

How do I test these cards?

They are not silly questions, if i was debugging, I would have asked the same thing.

THe molex connector is in there. The system was unstable without it plugged in. There are no jumpers on the board, My old DFI board had those. There is nothing in the Bios. I even updated the bios thinking that was the problem. It wasn't. The Nvidia control panel recognises both cards and SLI is checked off and running at 16x/16x and updated to the latest Firmware.

See I have tried all those things, and I've hit a road block. Hence I am confused as to why these cards just wont work together. Running one card with 1280x1024 on COD2 will get me 200 FPS .. With the same settings and both cards running in SLI, I get 50 FPS.

SIGH

-J

WHATS THERE TO BE CONFUSED ABOUT?

THE CHICKEN CAME BEFORE THEE EGG!

A supernatural force magically made a chicken, CMON thats a NO BRAINER!!

THE CHICKEN CAME FIRST!!

Just like that same force made ADAM AND EVE.

Hi.

I also had the same problemsetting up my two 7800's in SLI.

Your mobo is the same as mine so is capable of 16x/16x.

You have installed the "bridge connector"??

Anyway. My problem was all within the control panel.

I had to go into advanced 3D settings and manually check every setting.
It turned out that although the mobo detected the set-up and asked me to enable SLI it hadnt really done so.


Double check your 3D settings and if you are unsure as to what a certain setting will do just right click over the setting description and it willl give you a brief but handy drescription of what you are enabling/disabling.
Check refresh rate isnt locked either, failing that, try a fresh install of your graphics drivers and also check you have the latest chipset drivers while you are at it!!

You have probably done all of this already but there you go.

I also noticed when I played Company Of Heroes (and a few others) that if I had the setting I wanted eg- AFx8 AA-x16 as opposed to "application controlled" it ran really badly!!
So if I set it to app controlled it would be brilliant and my prefered setting made it run terrible.
The game silent hunter 3 is the exact opposite!! that game prefers you to set up your AA and AF etc from the control panel instead of app controlled!!

Its trial and error mate!!

Hi soberpyro,

I guessed you would have tried my suggestions but I had to ask because you never know!!
Didnt intend to patronise ya!!

Although only a handfull of games are optimised for SLI which may affect performance??

As it happens I have also decided to sell both my cards but to poor(ish) performance, the set-up just didnt seem to work.
I found it was a bit hit-and-miss so I have decided to sell both cards on e-bay and plump for the 8800GTX factory overclocked version.
It wipes the floor with anything around at the moment.
ATI are due to release the R600 version which should be good but I believe NVIDIA have got an ace up their sleeve with the 8900!!
We shall see huh??

Just an after-thought really but I imagine you are running the latest BIOS - 1303 and chipset - v-6.82??

You probably are, I get the impression you know your stuff.

P.S The one thing that confuses me though is the load times being longer??!!?? I will have to look into that one.
I noticed a significant increase in load times!! (although that is probably down to my processor and amount of memory)!!

How big is yoru Power supply?

it may be that it has enough power to run 1 but not both.

All the signs kinda point to them not getting enough power.