Good Performance Hunting

[Bealdwine]

As we all know STEP is mainly about modding Skyrim up to look as yummy as possible, but that comes at a cost even for the highest end PC rigs.

Here is a space to add in all those little tricks and tweaks we use to (re)gain that lost FPS and counter that stutter - there has been extensive chatter on this topic in previous forums so it may be appropriate to bring some of that knowledge over here.

 

@zMan On the topic of our previous talk about using DDSopt to 'correct' and reduce the VRAM load of textures. Have you seen this? Optimizer_Textures?

I'm testing it now (medium setting with resize @ >1024) as I had only run the vanilla and HD DLC through DDSopt previously. It is certainly less intimidating for newer users than the other option. I wondered if you could see any flaws in its implimentation?

[MontyMM]

This is well worth revisiting Bealdwine. I might be a good test subject for the efficacy of texture optimization, with my older hardware and 2 x 896mb GPUs in SLI. Unless Z denounces the app you mention, I'll give it a try and see what I get.

[Bealdwine]

The would be cool Monty :) If you are starting from scratch - unpacking the vanilla and HD archives, etc - it will take quite a while to run. As I had already done those through DDSopt it wasn't too bad for me. It mostly concentrated on the mod added textures which I hadn't optimized before.

 

I'm still in the process of testing but haven't noticed any major degradation in texture quality or glitches... yet. Load times have improved slightly and the instances of stutter or freeze have reduced noticably. I wish there was an ingame FPS counter as running anything else to get this would effectively give a false reading as I use Game Buster to reduce CPU load - shut off unneccesary services, etc - while playing. So all I can say 'subjectively' is that I notice a difference in performance without an apparent negative in quality.

 

Please let us know how you get on.

[z929669]

It looks like "Optimizer Textures" has some some nice features if it properly handles textures:

 

- Compress to DXT1c image without mask.

- Compress to DXT5 image with transparency.

(no compress if image/TGA is smaller)

(no compress for DXT3 if image is DXT5)

- Resize 16x16, if image is pattern (not lost quality)

- Make Textures whit mipmaps (only when compressing)

(no mipmaps for icons, menu_*, bookart)

- Delete BMP or TGA if exist DDS with same name.

- Delete Thumbs.db and others unecessaries files

- Remove alpha channel, when full covering a image.

 

The mod author (apipino) is Brazilian in seems, and it sort of shows in the lack of doc and difficulty following what is there. I put in a question about the app to Ethatron asking him to comment.

 

For now, the only way to test is to ... well, test :D (and take a lot of screens).

 

From the one compare screen posted on the site, it is a noticeable diff in both FPS and image quality (better for the former, slightly lower quality [iMO] for the latter). Some of the features look really interesting. The author need to update the mod to a true Skyrim port though (see ini and exe icon). He also would do well to team up with a native English speaker for the En version.

 

I definitely think that it is worth doing a compare using the vanilla textures as I have done with DDSopt (using Ethtron-confirmed and revised settings). I will add this to my to-do list. I will not really be playing SR for awhile anyway, as I am too into the WB guide and game optimization now :P

[z929669]

Useful insights into DDSopt straight from the horse's mouth:

Post1

Post2

[MontyMM]

I ran it on my untouched STEP installation. Didn't take too long - long enough to make a cup of tea. The results look good.

 

It claimed to have reduced textures by 315mb. In game I have noticed little difference in visual quality. There has been a clear reduction of stutter, particularly when turning 180 in a complex area, and a reduction of fps dips, rather than a boost to the upper limit . This is hard to quantify, as you say, but I'd testify to it under oath.

[z929669]

Some posts from the Nexus:

 

@montymodmonster

Thanks for the heads up. I think I'll do that backup of the textures and try it out, and report my findings, I'll also post my rig and settings, try to help other that might have similar machines to me.

 

Off the top of my head:

2gb ram (I think this might be my biggest problem)

x2 9600 gt's SLI'ed 512 mb ram each

Pentium quad core,

 

it's been a few years since I built it, I'll look into the hardware and get memory speed and proc speed after I run the test.

 

 

@roadside_fury

 

I'd almost guarantee that the memory on the video cards is the problem. When Z was doing some testing a while back, there was good evidence that the memory on cards in SLI don't combine to give you double memory. That's to say, each card loads all the same data into memory to do its half of the work, so 2 x 512mb cards still gives you only 512mb effective total, because they mirror each other. I have the same situation with two 896mb cards - it's very disappointing!

 

I have to cut back on some textures, and certainly 512mb is too low to run all of STEP, possibly even if optimized. If you were tempted to upgrade, that's where I'd start.

 

 

Yeah, I need to upgrade, but the mobo i've got is limited to an older memory speed, so by the end of the day, its best if optimized to run as i've got it, then when I build my new rig, I can run STEP with all the full texture packs, go high res, and get that super AA.

 

[z929669]

Second batch from the Nexus:

 

@MontyModMonster

 

You're correct in saying the memory doesn't combine. Both cards load the same data into memory. I REALLY wish they would find a way for SLI or Crossfire to combined memory. But from what I understand it's a bandwidth issue due to how fast the card can read it's own memory vs passing it over PCI-e

 

GPU Memory has been my biggest issue with texture mods. I have a 1gb card so I have to pick the medium level texture mods in most cases.

 

I've fine tuned my mods to the point where I'm normally running about about 1015mb used. There are some areas where it will max memory and stutter for a second but I can live with that due to how great the game looks.

 

I'll bet once all the mods start to mature the devs will find ways to optimize them to give us a great looking game with less of an impact.

 

Any idea what this texture optimizer is that I've seen people mention? I don't keep up on the comments and I saw a few people mention it today.

 

 

 

@MontyModMonster

I REALLY wish they would find a way for SLI or Crossfire to combined memory. But from what I understand it's a bandwidth issue due to how fast the card can read it's own memory vs passing it over PCI-e

 

You are correct in your implication that system RAM is slower than dedicated, on-card VRAM... MUCH slower, so that is not even an option for video memory needed instantly and on the fly. System RAM is very nice for 2D graphics though, just NOT 3D

 

Your chagrin point about SLI/X-fire VRAM not being additive but rather mirrored is a bit off the mark though. We WANT it to be mirrored, because that is why two cards are better than one. Each has an exact mirror in memory, so that the GPU of EACH can handle part of the load (like RAID0 versus single drive). Theoretically, we should get 2x the FPS gain from 2x cards in SLI; however, we are limited next by PCI-e in that each 16-pin card can only utilize 2x8 pins (not 2x16 pins), so the actual increase is not 200% but more like 120-130%.

 

In my testing, I estimate that the maximum safe VRAM load before stuttering will occur is approx 1.5x VRAM (for either single or SLI). The reason (I think) that you can exceed on-card VRAM by 50% again is because at any given picosecond the probability that the game will need 100% of the VRAM stored on card OR in system RAM is essentially zero. This is likely because on-card VRAM passes RAM it is not using at a given picosecond to the system RAM, and if the amount of VRAM passed to system remains at 50% or less, then probabilities work to game's advantage (if we trust driver memory management).. i.e., there will always be significantly more than a 50% chance that any given texture currently in memory will be in VRAM rather than system RAM. As you exceed 1.5x VRAM in textures, this value approaches 0% and you begin to notice stuttering.

 

This is all just my theory based on the numbers I have watched under varying conditions in game and the reality of current VRAM and system RAM load. I am not graphics hardware expert, rather I like to think that I am more a rational and logical nerd of sorts.

 

[Mardread]

Ok, So my system specs have changed quite a bit. I now have the following:

 

i5-2500k (new, up from i5-750)

16GB 1600MHZ DDR3 (new, up from 8GB 1333mhz)

GTX 560TI (old card)

 

Now the specs may seem minor in the way the computer works, in fact my WEI only went up 3 points to 7.5. The performance gains in Skyrim were tremendous. Not so much from the additional memory, but from the increase in power from the CPU. Yes the second generation is almost 2x faster than the 1st generation i5. The 560TI is now the bottleneck of the system. To do all this though, I had to change motherboards.

 

Now I still have the same issues with SSAO that I have had before (using TC recommendations from the guide). Reflective surfaces are too grainy and pixelated. Reducing the LOD Bias does not fix the issue. So I switched to a different method of using Sparse Grid Supersampling. It is a lesser form of SSAO with a better performance.

 

 

With these settings through nVidia Inspector, you have to set your Skyrim Settings to 4 or 2 for Anti-aliasing and 0 for Anistropic Filtering.

 

For the LOD Bias, here are some general rules:

 

LOD bias = -0.5 * log2(samples)

 

2x SGSSAA: -0.5

4x SGSSAA: -1.0

8x SGSSAA: -1.5

 

I have a couple of great references to help me figure out the proper way of doing this:

- NeoGAF PC Gaming General Performance Tweaking Thread

- Natural Opinions

 

Sorry, I do not have anything for ATI Cards, though the principles should still be the same. I think. I average around 45-50 fps in game right now, except in Whiterun where it gets down to 25-30 (blame Beautiful Whiterun). I can attribute the better frame rate due to the better CPU.

[Bealdwine]

@Mardread

Thanks for that (oh I wish I could afford an upgrade/rebuild :( ) I'm going to try those settings on my older card and see how it fares. I am already using the Sparse Grid Supersampling (can't remember now where I found out about that but works for me) and as TC is saying that SSAO has been borked by update 1.5 perhaps that one still works ;)

 

Which driver are you running? 296.10 WHQL or a newer beta driver?

 

I notice you still use the CoD:MW setting for Ambient Occlusion. Has the newer nVidia driver still not improved on this?

Also you don't seem to be forcing AF through the card which I thought was the reason to turn it to 0 in the game settings?

 

I'll update here if I hit any glitches.

[MontyMM]

Just a thought Bealdwine (any possibly others) - if you have an nvidia card and a motherboard with a second PCIe slot, you can use this little app to enable it for SLI, and stick in an old matching card.

 

https://www.techpowerup.com/forums/showpost.php?p=2414995&postcount=1

 

That's what I did a while ago. I enabled my ancient non-Nvidia motherboard (Asus P5W DH) for SLI, then bought another second-hand geforce 260 GTX from ebay, for peanuts. Combined with Skyboost, it makes a pretty good fist of running Skyrim, hovering around 45 - 50 FPS most of the time. Those older cards aren't far behind the current ones when you double up.

[Bealdwine]

Thanks Monty that sounds like a good interim plan while funds are tight - I run on a P5N32SLISEDeluxe so iirc there is already 2x PCIe x16 and an SLi 'switch' - I had totally forgotten about :facepalm:

 

...now the only problem is if they still do the 1Gb 8800 GT card! (and can I afford one of course ;) ) The best option alternative I've found was a single nVid 560Ti 2Gb @£209 but any other upgrades will really need a mobo-up re-build which will set me back a min £650 even for an i5 base (that includes an SSD and graphics card tho' - so not bad, just outside my pocket atm).

 

Look out eBay here I come.

[Mardread]

I am currently using the latest approved drivers from nVidia. I use a performance based look on my system to ensure that I get good FPS with quality visuals. It is a minor trade off which actually looks pretty good.

 

As far as the AF, yeah, I messed up there. Good catch. I must have missed it after I installed the new drivers... I will get some posts and run fraps to get a good reading of FPS. That will make a huge difference in my FPS.

 

BTW, my resolution is 1920x1080.

---

Ok, after fixing my settings:

 

 

With in game AA Settings set to 4 and AF to 0:

Whiterun: 25-30 FPS

World: 35-45 FPS (Depending on where you go)

 

With in game AA Settings set to 2 and AF to 0:

Whiterun: 35-40 FPS

World: 40-50 FPS (Depending on where you go)

 

I do run Beautiful Whiterun and Better Villages so my performance hit is going to be pretty high. I suggest using the without Smoke and Dust version of Better Villages because it can put a drain on your system. I was down to 20 FPS in Riverwood, with the other version, I was around 25-30. Not great, but playable.

 

With as many mods as I have, this is actually quite impressive. Next, I will try to run a full SMAA as the guide suggests to give comparative numbers on my system.

 

Quick Edit Here. Want to give you all some screenshots from Whiterun:

 

Shot #1

Shot #2

[stoppingby4now]

Awesome resources Mardread. I've been looking for more definitive information concerning such matters, but have always been disappointed. Though, one site that the first link does point to is German...he says it's easy to follow...yeah.

[Mardread]

Gonna add some more screenshots of whiterun:

 

Shot #1

Shot #2

Shot #3

Shot #4

Shot #5

Shot #6

 

My system specs again:

i5-2500k CPU

16GB DDR3 1600mhz RAM

GTX 560TI GPU

1920x1080 Resolution