Hello friends, I've found a way to fix the fps drop in dungeon/cave/indoor area.

Usually when you look at certain angle, your fps will drop. For example when you escape from Helgen keep, there are several angle that will drop your fps, look at the screenshoot below.

[img]http://img.techpowerup.org/111225/B-Heigen.jpg[/img]

Now, to fix this issue, put these command into your Skyrim.ini file and save it.

[LightingShader]fSpecularLODFadeEnd=0.0fSpecularLODFadeStart=0.0

Look at the fps boost after I put these command.

[img]http://img.techpowerup.org/111225/A-Heigen.jpg[/img]

I found out these command turn off reflection from object, look at the screenshoot below to compare.

Without tweak :

[img]http://img.techpowerup.org/111225/B-Ref.jpg[/img]

With tweak :

[img]http://img.techpowerup.org/111225/A-Ref.jpg[/img]

There are no candle reflection on the Jug and Alto Wine.

My spec is very low
Notebook
i3 2310M 2.1Ghz
2GB DDR3
Nvidia GT 520M

I played this on High settings with AA off, AF 16x, shadow turn to low, max actor and grass distance , I got 20-30 fps in town and rarely drop below 30 fps in indoor/cave/dungeon anymore with these tweak.

Good day friends, enjoy the game.

P.S : Sorry for bad english.

I'm wondering whether anyone knows what the default values for these are, so that I could try and see which ones boost performance the most while not being entirely switched off.

I think this is a good find. Well done.

People should always check their FPS before making the changes though using Fraps like you did. There is a seperate issue where you get stuttery graphics in the same locations even though your FPS has not dropped, particularly when using a high end Radeon graphics cards, that can be fixed without losing graphics quality.

Its important to find out which problem you have before you fix it so you don't uneccessaraily lose graphics quality.

You can see that Helgen screenshoot above, the first one(without tweak) have more grass on the wall, I found out that this grass thing and missing window I mentioned above is because
fDecalLODFadeEnd=0.0
fDecalLODFadeStart=0.0
I deleted this from my Skyrim.ini file, the grass on the wall and missing window show up with no performance hit, and I tried to delete them one by one and see what happen, I found out that you only need to put
[LightingShader]
fSpecularLODFadeEnd=0.0
fSpecularLODFadeStart=0.0
to gain fps boost.

[LightingShader]
fSpecularLODFadeEnd=0.0
fSpecularLODFadeStart=0.0

Do you know what these are supposed to be doing exactly? I'm theorizing they have something to do with the level of lighting away from the source. Also I was looking around for these settings and similar ones, so if you feel like tinkering more with your .ini, you can try these ones below.


[Display]
fLightLODMaxStartFade=1200.0000
fLightLODMinStartFade=200.0000
fLightLODRange=500.0000
fLightLODDefaultStartFade=1000.0000

Warheat, thank you!

I use a strong 'business laptop' with a poor GPU.

i7-2620M @2.70 GHz, 8 GiB RAM, SSD, Win7P 64-bit and - here's the poor part - NVS 4200M. The Nvidia name doesn't tell you it's a GF119 GPU, roughly akin to a GT 520M.

Your tweak, which has to do with how much reflections and 'glinting' one sees (and how far one can see it) from lightsources in reflecting surfaces (like bottles, metal barrel bands etc) has vastly improved my indoor FPS.

However, I did not like the totally dead look we get from a 0.0 value. So I experimented with a large number of different settings - measuring FPS and taking screen shots.

The lowest I could go, while retaining the FPS speed-up, and still getting eg bottle reflections at a distance of about what in real life would be ca 1.5 to 2 metres is:

[LightingShader]
; Original specular values have a HUGE indoor impact on FPS(light reflections):
;fSpecularLODFadeEnd=0.1000
;fSpecularLODFadeStart=0.0900
; The lowest I can go, while still retaining light reflections in nearby bottles:
fSpecularLODFadeEnd=0.0004
fSpecularLODFadeStart=0.0002
; This also gives a great FPS speedup in dustfilled (particles) caves with lights.

Since for example that Helgen corridor you showed in your comparison screen shots mostly lack any normal reflecting surfaces, I can only speculate that the dust somehow reflects the candle lights. Prior to this tweak I had 13 FPS there. Now I get 26 - I run very custum .ini-s for a High-Plus graphics experience, only shadows are at a custom Medium.

So once again, thank you.

These command affect reflection from light/candle, look at the screenshoot I posted above to compare .
Like LinUser said, I think the reflection also affect dust, that is why when you're in foggy/dusty area like cave/dungeon. Sometimes your fps will drop.

I tried to played around with these settings, weird for me. I still got no reflection with

fSpecularLODFadeEnd=0.0004fSpecularLODFadeStart=0.0002

and no performance impact in Helgen.

[img]http://img.techpowerup.org/111225/noref.jpg[/img]

the lowest I could go to get reflection is

fSpecularLODFadeEnd=0.0050fSpecularLODFadeStart=0.0025

But when I go to Helgen, I only got around 24-25 fps(30-32 fps if I turn it off), that is like 5-6 fps impact. But still better than since I only got 14-15 fps on default settings.

[img]http://img.techpowerup.org/111225/ref.jpg[/img]

Ah, but you _do_ get some reflections with my values. Compare the first, very dead, bottle picture you posted (A-Ref.jpg) with this one you call noref.jpg Quite a difference. That I get full reflections with those values and at such a distance probably has to do with other settings. How's your fSpecularLODStartFade in SkyrimPrefs.ini ? I've got:

fSpecularLODStartFade=1000.0000

That value is from a default High setting. But both my .ini files are heavily edited, and include eg values that effect draw distances way beyond what is possible with the ingame slide configurators. I like being able to see enemies that are several kilometres away, even though they only might be a couple of pixels high

It seems like people have to find their own sweet spot with this specular thing (FPS versus reflection distance/amount). But now at least there are some base values to compare with. I'm very satisfied with 26 FPS in the Helgen corridor and bottle reflections up to a couple of metres.

yeah, you're right, I just realized they are quite noticeable
My fSpecularLODStartFade default value is 200.0000

I'm still playing around with the value. Trying to find a way to lower the dust/fog effect. It seems they have a lot of performance impact as well.

That's interesting! Thanks warheat!

I'll try your settings, but I think my problems are different, I fixed all my indoor/dungeon fps drops by lowering shadow resolution from 4096 to 2048, so my kind of problem are those damn shadows....

Sorry for off topic. But I have this issue. No FPS lost, only some stuttering (especially in 1st person). Could you please tell me where to find this fix?
I have an ATI 5870 Matrix; 2 GB GDDR 5
Running the latest patch.

warheat, man I love you, I tried a thousand ways to remove lag in the interior, but none of them worked!!! But when I finally tried this, lag is completely gone!!! thanks a lot !!!!

Thank you so much OP! Also Thank you Draskozli for necrobumping.

http://www.gamesas.com/topic/1351011-wip-interior-shadow-lag-fix-proof-of-concept/

Could also give this mod a test. Disables some torch and candle shadows to improve performance. Might help, depending on your machine without the need to reduce or disable specular lighting.

There's a similar mod on nexus that disables all lighting shadows for the lower end machines. Something else to try anyway.

Hey guys! Thank you, nice additions. They really help me to improve [censored] performance in my laptop!

@mindofmike: "There's a similar mod on nexus that disables all lighting shadows for the lower end machines. Something else to try anyway."

Could you let me know which mod are you talking about? I need to disable all lighting shadows... when I fight with mages, fps go really down :-S