Are you using the latest NVIDIA video card drivers?

Yep newest drivers with clean install with precision all shut down

What, you didnt but the $99 DLC/Support? It will fix ya right up!

I had some issues with D3 until I set Max Foreground FPS to 150 and Max Background FPS to 30, and I set Shadow quality down a notch to medium if I remember correctly. Otherwise the game was horribly stuttery and laggy. I'm running the 331.82 drivers too, by the way. With these set, it's buttery smooth on two 760s. Hope this helps some of you!

Killmur
Yea it seems Blizzard has a real bad habit of implementing the worst shadow settings possible in their games. Although the same can be said for pretty much any game out there and not just Blizzard's games. Seriously how is it that in 2014 game companies STILL can't properly do shadows?

have you considered the complexity of a proper shadow?

I think it's something to do with whatever crazy online DRM they have going. I get some days where my game performs smooth as butter, and other days when I get so much micro-stuttering it makes 60 FPS look like 20.

Its blizzard. They spent 12 years making a sequal to one of the best games ever and didnt learn from their mistakes. For as many people that play the series theyve failed us all.

Simple as that. Youll just have to play with the.settings

cneuhauser
Everything is fine except I keep getting booted from their servers on a regular basis... something to do with their sloppy internet coding. They had the same issues in DII; can't remember how I fixed it, but it was down deep in the bowels of Windows.
 
Typical Blizzard though... and unfortunately, not as fun as Exile, or as creative. How long did it take them to create the DII clone? 5 years (whoops 12yrs as the post above states)? Another great company that went to trash.

Glad I didn't get a D2 clone. Didn't like D2 very much, Exile can keep doing their thing, if you want a D2 clone it's there.

@OP
try running the OSD in Precision, and monitor your GPU core speed as well as memory speed.  See if you are seeing them drop to idle speed and that coincides with the performance tanking.  If so, go into NVidia Control Panel - 3d Settings - Global Tab - Power Configuration (I think, I don't have it in front of me atm) - it is likely set to Adaptive change it to "Prefer Maximum Performance mode" I have found that fixed a LOT of FPS randomly tanking issues, especially in Blizzard games.
Basically, they aren't that demanding, so the card says "oh there's no load" and go to idle, FPS tanks, and GPU usage goes up due to the lack of clocks, ramps back up and corrects itself.
 
Also, for those of you who play D3 and have pre-Fermi cards, you can fix most of the performance issues by setting the in game PhysX to as low as it will go, that helped a LOT for some people I know with older systems.

boylerya
I remember getting 40+ fps even when Belial is in his second form using an i7-860 @ 3.8Ghz and 2x GTX275 1792MB SLI.  Max settings @ 1600p.  I havent tried the expansion yet because I was so disappointed in the final difficulty.
Although I do remember some crazy slow downs in one specific area in the beginning of Act 3 with all the fire.

The difficulties got revamped with Patch 2.0 as well (Inferno was totally BS pre nerf though, I agree)

I haven't had any issues at 5760x1080 with the highest settings. Maybe uninstall and reinstall the game. Are you connected to the Internet with a wire or wireless?

seth89
I haven't had any issues at 5760x1080 with the highest settings. Maybe uninstall and reinstall the game. Are you connected to the Internet with a wire or wireless?

i have reinstalled the game, done complete windows reinstalls, and connected through a wire
 
seems to be running ok right now but the performance issues is just so random and as i said before started the INSTANT they updated the game for reaper of souls so i guess ill have to deal with it and hope whatever is now broken with working on my system gets fixed at some point lol

I still want my money back for diablo 3....

I have not run into the same surround issues as before, everything appears to show up properly, however the main menu still looks odd (missing graphics) on side monitors. 

Game runs amazingly well for me. I just started playing on last Thursday and have enjoyed every minute.