I did loads of research before I bought another GTX 780, and almost everywhere I read anything from, almost all people said you will see gains going SLI as long as nothing else is holding you back or limiting your system like your CPU. I have a 3570k overclocked to 4.2Ghz with an H100i. It is my impression that Skyrim is well optimized for SLI.
I will state this. This is my first time going SLI. I do have SLI enabled through the Nvidia control panel and confirmed both GPUs are working with Precision X while in game. I still may have something wrong.
These framerates are from as soon as you enter Whiterun, and I have many mods that affect Whiterun as well as mods that ad NPCs, and loads of texture mods.
(Framerates only changed 1-2fps if am running an ENB or not.)
Framerate without SLI = 20
Framerate with SLI = 18
I was hoping to see at least a small increase at this area, like 10-15 at least, but not a drop.
I have searched online on if there is any setting that you manually have to turn on to enable SLI in game, but everything I read is from 1 or 2 years ago, from like version 1.2 or 1.4 of Skyrim, and the things stated no longer apply, so I assumed it was implemented by default in the later updates.
Also, from monitoring them in game, my GPU usage maxes out around 50% and my CPU maxes out around 60%, not sure why so low even though my fps is so low.
I have also tried each of the available 780 drivers, oldest to newest, no changes.
 
My system:
Windows 8 64-bit
AS Rock Z77 Extreme4 Motherboard
2x EVGA SC GTX780 3Gb
i5-3570k @4.2GHz
H100i CPU cooler
ASUS 1920x1080 Monitor 60Hz
Some SSDs for OS and games
 
Any advice is appreciated. 
 

vram is all ways a issue with nv sli ether now or later
I keep msi-ab running on my g13 lcd to catch it going over before a game crash.
but only had issues with my last 580sli 1.5 gb had bf3 come to a stop going from 1920 x 1200 to 1440 same settings,
but with all your mods it wouldn't hurt to monitor games vram usage.
 
I guess for now just use msi-ab until evga releases a up date
use the osd to monitor vram if it hits 3071 ish mb you need to lower some thing.- if you have a game slow down
same vram usage and no slow downs your good as the the game is just preloading.

YunGrey
This is what my vram usage looks like in game. It is maxing out on one card, but is the second card supposed to be doing nothing? When I mean loads, I mean loads of them, but in this area the only ones affecting it should be Skyrim HD 2k Textures, which alone shouldn't cause this massive of a problem.

It doesn't look like SLI is enabled properly.

YunGrey

HeavyHemi

YunGrey
This is what my vram usage looks like in game. It is maxing out on one card, but is the second card supposed to be doing nothing? When I mean loads, I mean loads of them, but in this area the only ones affecting it should be Skyrim HD 2k Textures, which alone shouldn't cause this massive of a problem.
 

It doesn't look like SLI is enabled properly.

Is there anyway that I can check if it is properly enabled? I have it enabled in the Nvidia control panel, but I haven't seen or heard of a way to enable it in any Skyrim settings, if that's even a thing.

You don't need to enable it in games. What I can see of the graph you posted, your memory clock on GPU 2 is not increasing under load which means it isn't being utilized at all. Have you tried running a bench like Heaven 4.0 to see if both GPU's are being utilized? I believe we need to make sure SLI is working properly prior to worrying about individual game performance issues.

HeavyHemi

YunGrey

HeavyHemi

YunGrey
This is what my vram usage looks like in game. It is maxing out on one card, but is the second card supposed to be doing nothing? When I mean loads, I mean loads of them, but in this area the only ones affecting it should be Skyrim HD 2k Textures, which alone shouldn't cause this massive of a problem.
 

It doesn't look like SLI is enabled properly.

Is there anyway that I can check if it is properly enabled? I have it enabled in the Nvidia control panel, but I haven't seen or heard of a way to enable it in any Skyrim settings, if that's even a thing.

You don't need to enable it in games. What I can see of the graph you posted, your memory clock on GPU 2 is not increasing under load which means it isn't being utilized at all. Have you tried running a bench like Heaven 4.0 to see if both GPU's are being utilized? I believe we need to make sure SLI is working properly prior to worrying about individual game performance issues.

I did benchmark it when I first set it up. These are the benchmarks when SLI was NOT working in game. Not sure why switching the SLI bridge over, then back, enabled it in game. 

HeavyHemi

YunGrey

HeavyHemi

YunGrey

HeavyHemi

YunGrey
This is what my vram usage looks like in game. It is maxing out on one card, but is the second card supposed to be doing nothing? When I mean loads, I mean loads of them, but in this area the only ones affecting it should be Skyrim HD 2k Textures, which alone shouldn't cause this massive of a problem.
 

It doesn't look like SLI is enabled properly.

Is there anyway that I can check if it is properly enabled? I have it enabled in the Nvidia control panel, but I haven't seen or heard of a way to enable it in any Skyrim settings, if that's even a thing.

You don't need to enable it in games. What I can see of the graph you posted, your memory clock on GPU 2 is not increasing under load which means it isn't being utilized at all. Have you tried running a bench like Heaven 4.0 to see if both GPU's are being utilized? I believe we need to make sure SLI is working properly prior to worrying about individual game performance issues.

I did benchmark it when I first set it up. These are the benchmarks when SLI was NOT working in game. Not sure why switching the SLI bridge over, then back, enabled it in game. 

Okay great. But is it working now?

Yes. I posted right before you made this post and I replied to it. Everything seems to be working correctly now just by moving the SLI bridge around. 

ty_ger07
You said:

. These are the benchmarks when SLI was NOT working in game.

I think he is asking "what about a picture of the heaven benchmarks for when SLI WAS working?". Since your two screenshots have the settings cut off, its hard to tell what the resulting scores pictured really mean.

This was when they were not working "in game". When I benchmarked it in Heaven, it worked fine, it just did not work in game. Everything seems to be working correctly in game now that I switched the SLI bridge around, except that there are no performance gains. 

ty_ger07
I think it is safe to say that we have no idea what you have changed half of the time between each of your status updates due to a lack of relevant information in either your text or screenshots.
 
So, may I ask again, what are your Heaven benchmarks now that it IS working in game?  Exactly the same?  Different?  If it didn't work in one, it shouldn't have worked in the other.  If it did work in one, it should have worked in the other.  A comparison is important since half of a story leaves a large part out.
 
But anyways...
 
 
Now, back to the beginning...
As I said up at the top, if you use up all your video memory, performance will plummet... and will plummet worse for two video cards than for one video card.
 

When I mean loads, I mean loads of them, but in this area the only ones affecting it should be Skyrim HD 2k Textures, which alone shouldn't cause this massive of a problem.

 
I am sorry, but it is a massive problem.  Your screenshots show that you are using up all your video memory which is causing your system to have to swap information back and forth between system memory and video memory; a process which eats up CPU processing time, system memory resources, motherboard chipset resources, PCI-E bandwidth, and video card GPU resources.  So, PLEASE, revert to standard textures so that your video card memory isn't completely maxed and compare.

Ok, I've got something going on with my game I need to figure out. I removed every texture mod I have installed and the memory usage has not changed at all. Thanks for your time and help.