» Mon May 28, 2012 6:43 am
Hey Renzee, your custom rez might be causing issues, but I don't know its just a guess.
But, I have some other info you might find useful. Indoor shadows cause a greater strain than outdoor shadows in Skyrim. You can test this by upping the iShadowMapResolution to 4096 in your .ini, in fact I wouldn't bother I can tell you now if you do that you will experience horribleness in indoor locations, especially on your rig. In indoor locations, shadows are better rendered and more demanding on your system the closer they are to the lightsource.
In your Arcadias Cauldron screenshot you are standing directly adjacent to the fire, which is the lightsource for that room. In your Helgen dungeon screenshot, you might not have realised it but you are standing directly adjacent to a lightsource too, its on your left hand side. I have been and had a look at that location, there are two lightsources in that room, one directly to your left, it is placed on the rocks below a hole in the ceiling that is on your left nahd side. Forward and to the right there is a torch, a second lightsource. Of the indoor shots you have provided the Helgen one has the worst FPS, it also has the most lightsources.
In your temple screenshot the lightsource for that room is in the exact centre of the room, but it is located right up top on the ceiling, and it is a high ceiling so the lightsource is farther away from you causing less lag, remember the closer to the lightsource, the worse the performance gets, the fact its high up is making the FPS better.
Outdoors is less demanding shadow wise, try running through whiterun and notice that (at least on mine anyway) when passing the torches they have no effect on your shadow. Your shadow is coming from the sun itself and so is everything elses. The sun is very high and far away so mI'm guessing this is why it doesn't causes issues like indoors, either that or shadows function entirely different outdoors altogether.
Look for the line iShadowMapResolution=x in your Documents/My Games/Skyrim/SkyrimPrefs.ini and make sure "x" is 512. I *think* thats the lowest it can go, maybe it can go even lower 256, but I dont know.
The line iShadowMaskQuarter=x in the same file can disable indoor shadows completely if "x" is set to 0. This will have some effect on making outdoor shadows look worse (probably) however if you want to find out if its shadows really causing your issues you can set it to 0 and shadows indoors should be turned off, so you can see your FPS without shadows.
Also, like a poster above says, some people have experienced slowdowns due to fog and smoke, but on my Radeon card I can honestly say fog and smoke do not affect my FPS by even 1. I assume its the light and shadow that usually accompanies smoke causing the problem, or something unique to lower end or Nvidia cards.
Edit: In fact I can't comment on the fog thing so ignore my note about that, my FPS is solid 60 in the Helgen dungeon (all through it), so if fog is affecting me I couldn't tell, if I had vsync off and frames went above 60 I could maybe see a drop for fog.