First of all, what is your monitor's resolution?
Second, what number on the slider does "fair" represent? Since the launch of Legion we've lost labels on the slider, and there are only numbers now.

I'm just curious because it helps to have these things defined for those who want to gauge their current hardware in terms of performance in Legion. I find it a bit excessive that 3 game clients using a "fair" slider setting were eating up 90% VRAM (assuming 1920x1080), and, currently, there's a bug in the game client which will force your game to use full ultra settings, even though the slider may say something else.

I also want to want to point out that anti-aliasing, a setting which can easily eat through video RAM and GPU performance, isn't affected by the slider. Were you using AA? I have helped fix issues for several people since Legion has launched by telling them to turn off anti-aliasing because, again, the slider doesn't.

Finally, do you have GeForce Experience installed? If so, GFE will automatically "optimize" the settings of the game, and because it has no idea you're multiboxing, it's going to result in absolute horrid performance.


Just some quick math for all involved... 60% of 8GB (8,192MB of VRAM on the 1080) is ~4.9GB total. Divide that up between 5 game clients and that's almost 1GB per game client at, what I'll assume since it wasn't mentioned, 1920x1080. We have to subtract a few hundred MB off of that total due to the desktop needing it, but, again, 800-900MB VRAM usage at fair settings does not sound normal to me.

However, three game clients at 90% of 4GB (4,096MB of VRAM on the 970) is over 1GB of VRAM per game client, which doesn't match up to the total usage of the 1080, so... it's a bit weird.

I just tested this out real quick on my machine, and here's what I saw at 1920x1080 for a single game client...

Code:
Idle desktop eats up ~600MB of VRAM, but I will subtract that from the values below.
Character selection screen eats up ~120MB of VRAM.
My normal, almost full ultra, settings (w/ 4x MSAA) are using < 1,000MB of VRAM.
Full ultra settings (w/ 4x MSAA) are using ~1.4GB of VRAM.
With the slider at 2 and MSAA disabled, I'm using ~550MB of VRAM max.
I ran around Suramar (the zone, not the city) for about 15-20 minutes picking up some mana and mining some ore, and my VRAM never surpassed 1,100MB.
1,100MB total - 600MB desktop = ~500MB of VRAM usage for the game client.

5x 500MB = 2,500MB + 600MB for the desktop, should be ~3,100MB, or 3.1GB of total usage for five game clients using a slider setting of 2.

Again, there just seem to be a lot of posts about who gets what performance (on all forums across the internet, not just this one), and people tend to leave out important details such as resolution. If you're playing at 2560x1440, then it's a different story, but at 1920x1080 your numbers seem a little high. My test was very quick and simple, and not in a true multiboxed setting, but should be close since I've done single game client versus multiple game client VRAM usage comparisons in the past.

I'll also say that I'm not trying to "lawyer" your or anything like that, but what's in my reply is what crosses my mind when I see a post/thread like this. :)