Hardware vs. part count

[Rosco P. Coltrane]

Ok, so since my GTX 560 went to oblivion after four days playing the KSP demo (and one after I bought the full game, really good luck:huh:) and I'm waiting for the new 680 to arrive, I've been reading the forums and watching videos on Youtube... And one thing I learned is this problem with too many parts causing FPS problems.

So, since all I have now is my "ho, boy, I wish I could be playing this game now" feeling and 3 million ideas to try when I get the new GPU installed, I ask: does any body has any info regarding this? I mean, how many parts are needed to kill what hardware, more or less? Is there a way to estimate?

My specs are an Intel Core i7 3770 at 3.40 GHz, 8GB of RAM and a GTX 680, so I was wondering how big will I be able to build.

PS: Yes, kind of stupid question, but I'm bored because I can't play. All I can do KSP-related is read the forums.

[bsalis]

The game is more CPU intensive from the (single threaded) physics. I don't think a better GPU will help.

[thirstyemu]

I have two macbook pros, one with a 330m and the other with a 650mx, but both have the same CPU (quad-core i7).

Apart from things like being able to ramp up the video settings themselves - like AA and scatter densities etc - it makes literally no difference as far as part counts go, you get to 1500 or 1600 and your screwed with either setup.

In fact, its unlikely to change massively until either the .20 update with all the ongoing streamlining or when the unity engine provides support for proper multi-threading as thats where the current bottleneck occurs.

[Sempiternal]

It's CPU based, and I have the same i7 as you, yet I don't get many problems. Then again, I've never built a ship above 150 parts.

[EndlessWaves]

I mean, how many parts are needed to kill what hardware, more or less?

The limit for running real time at a reasonable framerate (20fps+) appears to be 200-400, if you're willing to live with appalling framerates or launches taking much longer you can push it up to 1000 or so.

As others have said your new GPU will be unlikely to affect it as it's a physics limitation not a graphical one so expect exactly the same performance as with an i7-3770 and GTX 560.

[Simmo1404]

My specs are an Intel Core i7 3770 at 3.40 GHz, 8GB of RAM and a GTX 680...

Rosco, what motherboard are you running? Your CPU doesn't have an unlocked multiplier, but if you have a motherboard with the Z75 or Z77 chipset, then you can overclock the CPU by up to 4 bins (.4GHz). This should give a performance increase of about 12%.

[Brofessional]

Yea the GPU doesn't make much difference as long as you have a decent one.

I have two unlocked HD6950 2GB in crossfire, and the difference between minimum and max graphics settings at 1920x1080 is about 10fps. Like 90% of that is the texture filtering, I get maybe 1fps difference between no AA and 8x AA.

[HoY]

I run a 3770k @ 4.7 with liquid cooling, it's easier to push the multiplyer up for a game like this as it only uses a single core. Need to lower it down to 4.2 to run things like PP and use all 4 cores.

Agreed on the gpu. I have a gtx Titan now and it performs the same ad my 580 And 690 did in ksp

Plus I usually run at physics delta set to 0.03 for a smoother but slower gameplay. I can get upwards of 20fps on 1500 part launch, and since I record my flights for later use its simple to speed it up to real time in post processing.

Edited May 5, 2013 by HoY

[DaRocketCat]

Also Intel CPU's are much better for KSP than AMD ones, because they have much better per core performance, and KSP only uses one core.

[Rosco P. Coltrane]

Rosco, what motherboard are you running? Your CPU doesn't have an unlocked multiplier, but if you have a motherboard with the Z75 or Z77 chipset, then you can overclock the CPU by up to 4 bins (.4GHz). This should give a performance increase of about 12%.

It's an Asus P8B75 so I believe it can't be overclocked. In any case, with the hit I took with the GPU I don't have more money left for a water cooling system. (you won't believe the price of that thing here in Argentina)

So 100-200 parts... hmmm... I can live with that, I guess.

Also, I might have not used the search feature very well, cos now I was searching for "physics delta" and I'm finding a lot of reference to the parts vs hardware topic.

Thanks all for the answers!

[Simmo1404]

It's an Asus P8B75 so I believe it can't be overclocked. In any case, with the hit I took with the GPU I don't have more money left for a water cooling system. (you won't believe the price of that thing here in Argentina)

So 100-200 parts... hmmm... I can live with that, I guess.

Also, I might have not used the search feature very well, cos now I was searching for "physics delta" and I'm finding a lot of reference to the parts vs hardware topic.

Thanks all for the answers!

Yea, you can change the BCLK, but that's not easy, not normally advised and gives only a slight boost anyway. Don't assume you need to watercool though; on Intel's latest chips up to around 4.2GHz is fine with just air. I guess you'll have to just wait and hope for any physics optimisation the devs can manage. In the meantime, efficiency of launch vehicles and orbital construction are the only ways to reduce the size of the massive launch systems that cause you so much lag.

[DresCroffgrin]

I'm playing the game with a GeForce 660 @ 1228 mhz and an i7-3770k @ 4.1 ghz, and I've had launches of 200+ parts with zero lag. I haven't launched anything above about 250, however, so I don't know where the ceiling is.

[_Aramchek_]

Rosco, what motherboard are you running? Your CPU doesn't have an unlocked multiplier, but if you have a motherboard with the Z75 or Z77 chipset, then you can overclock the CPU by up to 4 bins (.4GHz). This should give a performance increase of about 12%.

What? I7's are multi unlocked.

I agree with the rest though, if you can, oc your cpu. (air cooled, hyper 212 with temps that never go above 65c)

I run my 3570k at 4.5ghz and I only have slowdown around the KSC because I have many, many land vehicles sitting around

Edited May 5, 2013 by _Aramchek_

[Krizzen]

This isn't the most ideal solution, but you could try lowering (or muting) the in-game sound and listening to some good music. It makes higher part count ships much more tolerable since you won't hear the sound skip, and... MUSIC!

[Rosco P. Coltrane]

The good thing about your idea is that it's free.

I guess I could OC, but given my luck (or lack of it) I better don't try to do anything dangerous.

But for now, I don't have plans for big stuff, so I guess I shouldn't have any major problems with lag. Specially considering that I just had completed my first docking tutorial before the GPU went bananas , so I have a long way to go. Time will tell.

[Camacha]

The CPU does not seem to be the only problem though. I am getting slow performance on bigger aircraft on a i5 2500K while all four cores are not loaded more than 50%. Somehow somewhere there is a bottleneck that is not the CPU and not the GPU.

[RatBeer]

how do i5 CPUs hold up against large craft? im getting an i5 3450

[Cooly568]

I can run around 300 parts with a I5 2500, GTX 550TI and 8GB of ram.

[_Aramchek_]

how do i5 CPUs hold up against large craft? im getting an i5 3450

Very, very well, especially if you clock them up.

[RatBeer]

I can run around 300 parts with a I5 2500, GTX 550TI and 8GB of ram.

yeh i rarely go over 300 part so it should be good.

[Camacha]

Very, very well, especially if you clock them up.

Like I said, the CPU is not the only problem. I get low frames with just 50% load.

[_Aramchek_]

Like I said, the CPU is not the only problem. I get low frames with just 50% load.

Cpu is the only real bottleneck in the game provided you have even a halfway decent vid card from the last four years or so, you can demonstrate this for yourself. Clock your cpu down to 2ghz and run a ship with a high part count, clock the cpu back up or to 4ghz+ and run the same craft.

You'll see the difference immediately.

[numerobis]

If you have just 4 GB, you're likely hitting swap if you do anything else at all on the machine. That's the principal slowdown that I face. With enough memory, it doesn't matter much how much you have.

I saw a report (lost in the purge, and anyway I doubt I could have found it) that KSP does an awful lot of disk I/O while running for unknown reasons, and that putting the KSP directory on a RAMdisk -- or presumably on an SSD -- would improve performance.

Finally, the particle effects given off by rocket motors apparently are fairly expensive. Someone had written a quick hack plugin to remove them and found a surprisingly big speedup.

[lobsterbark]

If you have a crappy enough gpu, you will get limited by it. My gpu is so bad, how fast a webpage loads is entirely limited by my gpu, connection speed doesn't matter.

[Camacha]

Cpu is the only real bottleneck in the game provided you have even a halfway decent vid card from the last four years or so, you can demonstrate this for yourself. Clock your cpu down to 2ghz and run a ship with a high part count, clock the cpu back up or to 4ghz+ and run the same craft.

You'll see the difference immediately.

Sure, but that does not explain why my CPU is about half loaded. With a plane of 353 parts, I get 8 frames per second, which is of course quite slow. Most people would think this is predictable due to the number of parts. However:

CPU - i5 2500K: total load ~30%, most loaded core sometimes at ~70%, often at ~45%

GPU - GTS 450 1 GB DDR5: load about 30% too, 838 MB of 1 GB VRAM used, memory controller at 21%

RAM - 8 GB DDR3: 6,45 GB of 8 GB used

As you can see, there is nothing obviously bottlenecking performance. All parts have actually plenty of performance to spare, but still the frame rate is dramatically low. Performance should be higher, but for some reason is not. KSP just seems to be incredibly inefficient in some way.