I don't normally hang around forums, but I had experienced the annoying Frame Skip and incredible lag in the presence of more than a couple NPCs. I have noticed a ton of you who have also complained about these issues. I found the "hacked" DXD9.DLL file** to solve the NPC lag problem, but it left the Frame Skip problem and made the game look like crap -- I'm used to playing on "high" setting. Well, I've have successfully been playing the game for over 4 hours now WITHOUT any frame skip or NPC lag <30FPS (even with 6 Legions attacking me).
Here is how I have been able to play the game with smooth frame rates on a sub-system-requirements machine on HIGH graphics settings (almost--minus the lights/specular LOD). I will provide a little background first:
----Machine Specs-----
P4 3.0GHz HT (pseudo-multicore for the illiterate)
1.5GB RAM
Radeon HD 3650 (overclocked to 750MHz GPU, 465MHz VRAM)
Creative Audigy 2 (sound card)
WinXP SP3
----First things First----
I'm not sure if this will be an issue for higher spec CPUs, but I found I had to disable the Steam In-Game Overlay by right clicking on the game in the Library->Uncheck the option. Also, I had to disable the Steam Cloud as it was bugging my save game numbering. Disabling both these earned me a good bit of FPS.
----The Frame Skip Issue FIX----
To resolve the frame skip issue using the RETAIL DirectX DLL file, you simply need to force the game to run at a higher refresh rate. Currently the engine runs at 64 ticks per second, but the engine forced the rendering to 60Hz. This means you will possibly miss 4 frames every second, and if there is lag it could be extremely noticeable and annoying.
To have the game engine render every world tic and FIX THE FRAME SKIP, go into: Catalyst Control Centry --> Display Options (under Welcome) --> 3D Refresh Rate Override: Set this value to your monitors natural refresh rate. (My desktop refresh rate is 100Hz, so I set it to 100Hz.) If your monitor isn't capable of anything above 60Hz, I'm sorry but this fix isn't going to work.
----The NPC Lag Issue FIX----
As you can tell, my machine is under the system requirements, but my video card is well above it. Regardless, this fix should work for anyone running an ATI card. This requires changing 2 catalyst control center options.
(1) Go to Catalyst Control Center --> "3D" option (under Graphics Settings Tab) --> Catalyst A.I. --> Advanced (move the slider all the way to the right, and make sure "Disable Cat. AI" is NOT checked).
(2) Cat Control Center --> "Mipmap Detail Level" --> Move the slider to "Quality" setting (and NOT "High Quality").
(3) (optional) I also found incredible performance boost by overclocking my video card using the Catalyst Control Center, but that is another topic entirely and you can cause the game to have weird graphical glitches if you overlock the card just a wee too much. If you have my card, the settings mentioned in the Background setion above should help you.
Hope this has helped. I know I love the game now. :fallout:
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** The hacked DXD9.DLL file is just a skinny wrapper to trick the game into thinking you have a lesser video card. I found it made the game look unacceptable.