Zotac GTX 780: Fallout 3 doesn't boost to maximum

Zotac has their own o'clocking utility (Firestorm). So I setup an overclocking profile that changes the base clock (I guess) to 1 Ghz and boots the power limit to 106% and the temperature to 84 degrees C. I raised the core voltage to 1.2V. But, when I run Fallout, Firestorm reports the max core frequency seen as 941 Mhz, which is the stock base clock for this particular GTX 780. The overclocking profile works for say, Far Cry 3 or Crysis 2, just not for Fallout 3. Why?

Have you checked the GPU usage at these points? My 680 doesn't boost if the usage is low enough and sometimes even drops to 2D clocks (For example this occurs in Garry's Mod).

Boost clocks are affected by two things... Power use and temperature. My guess is raising the voltage to 1.2 is causing you to hit the 106% power limit.

Please use MSI AB and see what it is showing.

ED, it never boosts at all when I'm playing Fallout3 -- it's stuck at 941 MHz. I think Badbonji might have nailed it, because when I check the GPU loads they're minimal, which is bizarre considering the game is running slower than molasses on a cold winter day. It does look like two CPU cores are seeing significant usage 90% or more.

I think I'm going to try to revert to an earlier, working version of my Fallout3.ini file and see if that makes a diff.

Is there anyway to force the GPU to run at the clockspeed you want it to run at?

I did it by editing my BIOS in Kepler BIOS Tweaker and setting TDP, 3D, and Boost clocks all to 1225MHz and RAM to 7600MHz. Don't touch anything else as the BIOS is pretty complicated. Now my 2 GTX 760s run at full clocks even in Freecell.

I don't see the point in doing that as you aren't seeing going to see any benefit - the GPU load should end up lower but with you will probably be using more power as the voltage will be higher.

I followed False Christian's idea and finally got my GTX780 to run at almost the clock speeds I set. I disabled boost, but even then Fallout 3 doesn't run at the core clock speed I set in Zotac's Firestorm o'clking utility. What's bizarre is that I can run Far Cry 3 at 4xMSAA, 4xSSAA (transparency), but can't do the same w/Fallout 3 because the game turns into a slideshow.
Fallout3 @ 4xMSAA, 4xSSAA(transparency) pegs the GPU load @ 100% too. Is the SM2.0 that Fallout3 uses really that inefficient?