JamesIceland

CPU Choices for P3D now and the future - Cores

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Hi all,

 

I've posted a similar question on the P3D forums but I thought I would ask the technical AVSim Gurus for some help on my new build.

 

I last built a PC for flight sims back in 2012 - I have a i7-3930k (6 cores) which I had overclocked to 4.3 Ghz and I have a GTX 780Ti. I was generally pretty happy with performance in P3D version 1 and 2 and it's been ok in v3 to a point.

 

As I have been researching I can see that my timing looks likely to coincide with:

 

1) a new Intel and AMD CPU battle - whilst this will be great for all consumers ultimately, it isn't helping me with my planning.

2) a new Intel and AMD GPU battle - I'm going to wait until later on the GPU side

3) a new P3D release (c. in the next 12 months), possible 64 bit and unknown other improvements.

 

I want to future proof - doing this with my last build has served me pretty well. Right now though I'm struggling to know how to future proof when 3) could have a big impact on my choice of 1) - I'm not worried about my GPU choice right now. Making the choice even harder is that I need to build this probably by the end of March as I'll be relocating to a place where the parts/importing of parts will be prohibitively expensive!

 

My understanding is that in order to get the best performance from P3D as things are today, I should look at getting a CPU that has a high clock speed/overclocking - core count is less important. If this is the case I would be wise to go for the latest 7700k? I know the i7-4xxxk was the ultimate but wouldn't see much point in getting an older generation.

 

With that said, I have been closely looking at the AMD news and in particular the talk of the 1800x 8 core processor. I know we will need to wait for benchmarks to see how it performs, and that the base/boost clocks currently look lower, but if there is decent overclocking potential on these chips, say to 4.5 Ghz plus, then are they looking like a more viable alternative to Intel?

 

Now for the hypothetical part - if we assume that a 64bit P3D is in our futures and that if (big if) in its life-cycle LM refines the code further to make better use of multiple cores, would AMD be the best future proofing choice? i.e. I'd get immediate good performance potentially in line with Intel now but with scope for more down the line? I'm also thinking along the higher multiple core line due to the add ons I use - things like ASN, ChasePlane, AivlaSoft EFB etc. Does this matter though?

 

I'm planning on coupling the CPU with the next gen NVidia 1080Ti/2080 or AMD Vega battle winner later in the year. I will definitely be waiting for the AMD CPU results to come in before doing anything. I just wanted to pick some fellow flight simmers brains as to thoughts on my upcoming choices. If AMD results are decent I'd seriously be leaning that way but perhaps someone could voice their opinion as to why this may be not be sensible? i.e. P3D code may never become optimised for multiple cores!

 

Any thoughts/discussion would be appreciated. It's certainly nice to have some choices but deciding whether to build for what we know today or what could happen in the future is a bigger struggle than it has been for a long time!

 

Many thanks

 

James 

 

 

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Your question is valid, though difficult to answer since no one here knows how the engine which P3D runs on will change over the next several years.  It could continue to be largely constrained by single-thread performance, or LM could find the magic bullet that allows the sim to scale across multiple cores such that performance now scales more closely to core count than clock speed.  Personally, I find the latter hard to believe and have recently purchased an i7 7700k rather than waiting for an 8-core Ryzen chip because:

1) I still run good old FSX (in addition to P3D and X-plane)

2) every current sim still runs better with a higher clocked, lower core chip than the opposite

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 Personally, I find the latter hard to believe and have recently purchased an i7 7700k rather than waiting for an 8-core Ryzen chip

 

That's a valid point - I think I will wait for 1 more week and see how the benchmarks look for Ryzen in terms of overclocking - i.e. how far they can be pushed. If a 6 or 8 core can get towards 4.5-5.0 GHz then they come into play more. Otherwise a 7700k with standard boost achieves the same.

 

One more week to go hopefully before we start to find out. Predicting what P3D is going to do is impossible - trying to build something that future proofs things without the information is very hard. I would normally wait for V4 and then decide but my time constraints mean that I will have to take an educated guess at some point (unless V4 comes out in the next couple of weeks).

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The 7700K will remain the king for Prepar3D, because of its higher clock speed and IPC compared to the 6 - 10 core offerings from Intel, as well as AMD Ryzen.

 

However, the question is whether you want to build a system today, and only consider how well it runs the 10+ years old ESP code base (P3D/FSX)? The future is multi-core, and if you plan on keeping the new system for as long as the old one (5+ years), downgrading to 4 cores seems like a backwards move.

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The 7700K will remain the king for Prepar3D, because of its higher clock speed and IPC compared to the 6 - 10 core offerings from Intel, as well as AMD Ryzen.

 

However, the question is whether you want to build a system today, and only consider how well it runs the 10+ years old ESP code base (P3D/FSX)? The future is multi-core, and if you plan on keeping the new system for as long as the old one (5+ years), downgrading to 4 cores seems like a backwards move.

 

Downgrading to 4 cores from the OP's current 6 core chip?  His 6-core chip is 5 years old.  The architectural and clockspeed improvements since that time outweigh the performance of the additional cores.  Trust me, I've made the comparison.  Even a newer 6-core chip like the 6800k, or the 5820k I have in my media server can be matched by a highly-clocked 7700k.  

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Downgrading to 4 cores from the OP's current 6 core chip?  His 6-core chip is 5 years old.  The architectural and clockspeed improvements since that time outweigh the performance of the additional cores.  Trust me, I've made the comparison.  Even a newer 6-core chip like the 6800k, or the 5820k I have in my media server can be matched by a highly-clocked 7700k.  

 

You're right - performance from a 7700k over my 3930k will be much improved - technology has certainly moved on.

 

I was just reading the Ryzen thread on here and I saw Linus's video this morning - the Ryzen 1700x and 1800x look really compelling choices. I am slightly concerned that XFR seems to maybe offer a 100MHz boost to around 4.1GHz - we will need to see how far it can be pushed once reviews come out on 28th or whether this is towards the max that can be achieved. I was interested to see the demonstration of the game (forgotten which) where he was streaming and how much more smoothly that ran with the low end Ryzen. Which leads me to:

 

I think I should point out that smoothness is key for me in my considerations, I'm not chasing a few FPS here or there (although I know the 2 are interlinked). I have been reading up on the multi-core thread topics on here (4 core vs 6 core vs 8 core and others) - views vary but there is an argument that more cores can offer smoother performance, especially when using add ons. Realistically when flying say a PMDG I have AivlaSoft EFB running (2 programs), ASN, TrackIR, ChasePlane, PFPX, maybe an virtual airline tracker and a web browser - hopefully with v4 P3D I won't need Process Explorer for VAS any more! In this scenario, sharing the workload across more than 4 cores must have an impact i.e. the sim has more space to run on it's on dedicated cores. 

 

I guess I need to figure out if an 8 core CPU like Ryzen at 4.1 GHz is going to run all these things more smoothly than a 4 Core 7700k at 4.7GHz+. If a 7700k may offer 10-15 FPS boost over Ryzen but then stutters when loaded up with add-ons then it's not going to be ideal. And the future could be multi-core - I would be gutted to buy the 7700k and then find 6 months down the line P3D v4 is better optimised for more core performance. 

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Downgrading to 4 cores from the OP's current 6 core chip?  His 6-core chip is 5 years old.  The architectural and clockspeed improvements since that time outweigh the performance of the additional cores.  Trust me, I've made the comparison.  Even a newer 6-core chip like the 6800k, or the 5820k I have in my media server can be matched by a highly-clocked 7700k.  

 

It's also 5 years of near-stagnation from Intel.

 

It depends on the application:

http://www.anandtech.com/bench/product/552?vs=1826

 

Taking into account that the OP's 3930K runs at 4.3 GHz, a 34+% higher clock speed than shown here, it's definitely more of a side-grade, and even a downgrade in certain cases (in Cinbebench multithreaded, the 3930K is nearly matching the 7700K, even at just 3.2 GHz, in Sysmark it would match the 7700K if OC'd to 4.3 GHz).

 

If only single-threaded performance matters, then the 7700K is a definite upgrade. On the other hand, in that case the Ryzen would merely be a side-grade. If multi-threaded performance matters more, then the 7700K would be more of a side grade, while Ryzen would be a significant upgrade.

Being based on an old code base, P3D falls into the first category, at least as far as version 3.x. So in that case, the 7700K would be a better choice.

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Being based on an old code base, P3D falls into the first category, at least as far as version 3.x. So in that case, the 7700K would be a better choice.

 

Exactly - therein lies the dilemma - what are Lockheed Martin going to do with the code for v4 apart from it being 64 bit as a best guess? Reading some threads on their forum they do occasionally mention that P3D does take advantage of multi core processors but it's never easy to find out by just how much it does.

 

Can they take advantage of more cores and is there incentive for them to do so? It depends what most users have in their systems I guess. The core target audience for P3D remains in the commercial space so I'd have no idea if they would be using supercomputer multi-core processors that LM may want to optimise the code for. 

 

Next week will give us more information, particularly if reviewers can squeeze a lot out of the Ryzen chips. That will be what swings it for me. 

 

I am also aware that my 3930k stands up pretty well - the benefit of going to a 7700k is clear from a single-threaded perspective as I'd be getting perhaps up to 5GHz from it as things stand today.

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It's also 5 years of near-stagnation from Intel.

 

It depends on the application:

http://www.anandtech.com/bench/product/552?vs=1826

 

Taking into account that the OP's 3930K runs at 4.3 GHz, a 34+% higher clock speed than shown here, it's definitely more of a side-grade, and even a downgrade in certain cases (in Cinbebench multithreaded, the 3930K is nearly matching the 7700K, even at just 3.2 GHz, in Sysmark it would match the 7700K if OC'd to 4.3 GHz).

 

If only single-threaded performance matters, then the 7700K is a definite upgrade. On the other hand, in that case the Ryzen would merely be a side-grade. If multi-threaded performance matters more, then the 7700K would be more of a side grade, while Ryzen would be a significant upgrade.

Being based on an old code base, P3D falls into the first category, at least as far as version 3.x. So in that case, the 7700K would be a better choice.

 

Out of those 30 benchmarks, Kaby Lake wins 25 (several test results are displayed in ms where shorter bars mean better performance).  Of those 5 losses, the average difference is around 10%.  I'm not going to calculate the average margin of victory for the other 25, the results are there for anyone to see.  Given that some of them are 50-100% faster on Kaby Lake, it's pretty clear what the faster chip is.

 

James, If you want to know what the fastest chip is for FSX, look no further than here: http://www.avsim.com/topic/329116-fsxmark11/page-51#entry3580381 If able, run the test on your system and compare to my results.  

 

As I said earlier, no one knows the future.  I can't promise you that Kaby Lake will be the faster chip from here to eternity, but it is faster (at least in FSX and P3D) today.  

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15 hours ago, TechguyMaxC said:

As I said earlier, no one knows the future.  I can't promise you that Kaby Lake will be the faster chip from here to eternity, but it is faster (at least in FSX and P3D) today.

Thanks Max - you seem to know what you're talking about for sure which is great and reassuring for someone like me who last looked at computer components nearly 5 years ago. I was so out of touch that I actually had no idea about AMD coming back until I started doing my research. I was thinking it would be a simple Intel top end (7700k) CPU and NVidia (GTX 1080) GPU choice for me. Now there could literally be a valid alternative choice in both areas - although I am likely to plump for a 1080Ti regardless of Vega this year. All of this is great for consumers. 

I was watching a few YouTube videos on Ryzen today and all were pretty much saying wait until they've had a chance to test things with overclocking - if they can squeeze real high clock speeds out of Ryzen with say a decent AIO cooler then that'll swing it I think for me. If over clock speeds are more like a max of 4.3GHz then I'm not sure I'll see much advantage over my current setup and will go for Intel. 

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Just came across this site which is really interesting:

https://siliconlottery.com/

I really want to get my temperatures under better control in the new build so I'd be very tempted with their delid service on a guaranteed overclocked chip - I'm going to write and ask them a few questions. Not sure what sort of cooler I'd need if I got a 5.1GHz chip for example! Was thinking of a Corsair H115i but I can see this leading to custom water cooling if I'm not careful...

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17 hours ago, JamesHongKong said:

Just came across this site which is really interesting:

https://siliconlottery.com/

I really want to get my temperatures under better control in the new build so I'd be very tempted with their delid service on a guaranteed overclocked chip - I'm going to write and ask them a few questions. Not sure what sort of cooler I'd need if I got a 5.1GHz chip for example! Was thinking of a Corsair H115i but I can see this leading to custom water cooling if I'm not careful...

Only 28% of the CPUs tested hit 5.1Ghz... Sounds like playing the lottery- gamble!  And even so, what they don't tell you is how do you get a-hold of one of the ones that can hit 5.1Ghz?  (humm) And, they don't tell you for how long that 5.1ghz will hold before crashing. So, it sounds more of a hype than reality. 

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Hi Joe,

Actually they do the testing and sell chips that hit those overclock points - you buy from them for a slight to high premium (depending on the overclock) and are guaranteed a chip that can hit that speed. I have been reading up on the guys there and some of the testing sites who have reviewed their chips and they are apparently legit and feedback is good. I emailed them some questions last night and they came back quickly with decent info. I'm not saying I'm going to buy from them but they're basically testing out the chips and selling those in the "silicon lottery" that hit the performance points i.e. the 28% for 5.1 Ghz or 7% for 5.2 GHz. Plus they do the de-lidding too if you want - again, reports back on this have been positive.

We will see.

 

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On 2/22/2017 at 10:04 AM, JimmiG said:

The 7700K will remain the king for Prepar3D, because of its higher clock speed and IPC compared to the 6 - 10 core offerings from Intel, as well as AMD Ryzen.

 

However, the question is whether you want to build a system today, and only consider how well it runs the 10+ years old ESP code base (P3D/FSX)? The future is multi-core, and if you plan on keeping the new system for as long as the old one (5+ years), downgrading to 4 cores seems like a backwards move.

Not quite the King or rather the king should move over. Recent testing on Ryzen 7 1700X SINGLE THREAD test against  Core i7 7700K   beats the latter. Of course it demolishes multi-threaded   Core i7 6950X  Intel’s flagship processor all $1700 of her.

  http://wccftech.com/amd-ryzen-7-1700x-6950x-7700k-cpu-benchmarks/

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5 hours ago, Lenny777 said:

Not quite the King or rather the king should move over. Recent testing on Ryzen 7 1700X SINGLE THREAD test against  Core i7 7700K   beats the latter. Of course it demolishes multi-threaded   Core i7 6950X  Intel’s flagship processor all $1700 of her.

  http://wccftech.com/amd-ryzen-7-1700x-6950x-7700k-cpu-benchmarks/

The next couple of days should certainly give us some more idea as to performance. I am leaning towards the 1800x Ryzen more and more - a couple of exchanges I have had with people in the community has suggested multi core optimisation is perhaps on the cards for both sims and games in the future - whilst this would be a guess and a risk to take I don't think it is that big a one. Performance and smoothness with a higher core CPU (with a higher LM3 cache) is certainly possible and the performance difference between say a 7700k and a 6 or 8 core CPU isn't going to be that big. Or I should say that I would probably not notice it. Particularly if running a lot of other external add ons. If we can get Ryzens that hid 4.4-4.6GHz say then that'll swing it for me.

If I do go that way I'll be sure to post up my experiences, that's for sure! Will be waiting for the reviews. The embargo is up today isn't it for reviewers?

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15 hours ago, Lenny777 said:

Not quite the King or rather the king should move over. Recent testing on Ryzen 7 1700X SINGLE THREAD test against  Core i7 7700K   beats the latter. Of course it demolishes multi-threaded   Core i7 6950X  Intel’s flagship processor all $1700 of her.

  http://wccftech.com/amd-ryzen-7-1700x-6950x-7700k-cpu-benchmarks/

I've seen you say this a couple times now.  You should be careful or you're going to end up disappointing yourself, and misleading others.  The result(s) you're pointing to consist of a single synthetic benchmark, i.e. not a real world application.  Performance rarely scales perfectly from synthetic to real-world.  In addition to this, a single data point means very little in the big picture.  Sure, Ryzen could be faster in this one test, and slower in 100 othres.  Wait for results on Thursday.  We'll know how it does for sure at that time.  

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17 hours ago, JamesHongKong said:

The next couple of days should certainly give us some more idea as to performance. I am leaning towards the 1800x Ryzen more and more - a couple of exchanges I have had with people in the community has suggested multi core optimisation is perhaps on the cards for both sims and games in the future - whilst this would be a guess and a risk to take I don't think it is that big a one. Performance and smoothness with a higher core CPU (with a higher LM3 cache) is certainly possible and the performance difference between say a 7700k and a 6 or 8 core CPU isn't going to be that big. Or I should say that I would probably not notice it. Particularly if running a lot of other external add ons. If we can get Ryzens that hid 4.4-4.6GHz say then that'll swing it for me.

If I do go that way I'll be sure to post up my experiences, that's for sure! Will be waiting for the reviews. The embargo is up today isn't it for reviewers?

I thought it was March 2 the actual release date.

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7 hours ago, TechguyMaxC said:

I've seen you say this a couple times now.  You should be careful or you're going to end up disappointing yourself, and misleading others.  The result(s) you're pointing to consist of a single synthetic benchmark, i.e. not a real world application.  Performance rarely scales perfectly from synthetic to real-world.  In addition to this, a single data point means very little in the big picture.  Sure, Ryzen could be faster in this one test, and slower in 100 othres.  Wait for results on Thursday.  We'll know how it does for sure at that time.  

Of course. But the original poster made it appear that the story was already a fait accomplis on Intel's chip. In fact, if anything, it's Intel's propaganda which should be told to "be careful". The point is the testing has just started and is being leaked out. No one should be writing this Ryzen off in single threaded tests just yet.

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2 hours ago, Lenny777 said:

I thought it was March 2 the actual release date.

You could be right actually - I thought there was an embargo of the 28th but maybe not.

On the P3D forums one of the software developers confirms that P3D does make use of more cores if you have them. I was also advised that a sweet spot would be 8 cores. I know there are differing opinions on this but I think for my other computer usage (photo/video editing) more cores will likely be beneficial. I think Max may have said this in mentioning he has a sim build and another for other uses? 

Just now waiting for NVidia's press conference to start to see what GPU I may be pairing with whichever CPU I go for!

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11 hours ago, JamesHongKong said:

You could be right actually - I thought there was an embargo of the 28th but maybe not.

On the P3D forums one of the software developers confirms that P3D does make use of more cores if you have them. I was also advised that a sweet spot would be 8 cores. I know there are differing opinions on this but I think for my other computer usage (photo/video editing) more cores will likely be beneficial. I think Max may have said this in mentioning he has a sim build and another for other uses? 

Just now waiting for NVidia's press conference to start to see what GPU I may be pairing with whichever CPU I go for!

"Uses" is not the same as "produces higher FPS".  P3D and X-plane can both use a lot of cores, but in most situations it won't help your frame rate.  Only when you have extreme amounts of AI can the additional cores make a difference compared to say a quad core chip.  

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13 hours ago, TechguyMaxC said:

"Uses" is not the same as "produces higher FPS".  P3D and X-plane can both use a lot of cores, but in most situations it won't help your frame rate.  Only when you have extreme amounts of AI can the additional cores make a difference compared to say a quad core chip.  

I understand. I think the differences I would likely see between the different CPU's may be negligible though. I am also thinking about future proofing in case future versions of P3D optimise things further. If it does go 64 bit that may open up in terms of AI Aircraft too so could be some benefits. I may be able to make use of more cores in other work I do too. We will see today/tomorrow with the first reviews likely to come in. 

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On 3/1/2017 at 10:40 PM, TechguyMaxC said:

P3D and X-plane can both use a lot of cores, but in most situations it won't help your frame rate.

Well Max, you have been pretty much spot on throughout. Having digested a lot of the information and reviews coming through it looks like the pendulum swings back in favour of an Intel 7700k build for P3D. The results coming in for Ryzen are somewhat underwhelming in real world gaming scenarios but look great for multi-threaded workstation use. There is probably quite a lot of early adopter issues being seen by the reviewers - it sounds like the full RAM potential is not unlocked, things like that. I watched a livestream today from Jayztwocents and he has received emails from AMD to disable x, y and z on the CPU's (and on Intels even) to get most performance i.e. it's not out of the box ready. Therefore for now, as you've been saying, in any meaningful gaming metric, the 7700k is streets ahead at stock clock speeds, let alone when pushed.

My only concern going with a 7700k build is future proofing and second guessing whether Intel will release something more interesting quickly or whether P3D v4 is suddenly going to be suddenly multi-core friendly. The two thoughts I would have on that are that:

1) If LM do go 64 bit does that mean they will automatically be making it more multi-friendly i.e. does one thing go hand in hand with the other or will the 64 bit optimisation be the big and only change

2) Even if they do go multi-core tastic, would I really notice a big hit with a 7700k for the next couple of years? i.e. am I suddenly going to be losing loads of frames and smoothness?

One thing that I have decided (and please feel free to chime in with thoughts here) is to use a spare networked PC to run a number of the apps I use when flying. Therefore my main sim build will be pretty much P3D only and I'm hoping to offload things like AivlaSoft EFB, ASN, ChasePlane and others to it. Theoretically this will free up the 4 core 7700k to focus on P3D pretty exclusively. Will this be a good move?

Getting ready to move forward now - I think the next build in a couple of years will be really exciting as I think the competition will be there from AMD once things get settled down - the next gen Intels and AMDs may be really good for us all.

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7700K + 1080 ti would be my favourite wehn I had to build a new system for P3D at the moment...

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Just now, swiesma said:

7700K + 1080 ti would be my favourite wehn I had to build a new system for P3D at the moment...

That is exactly what I'm going for - just ordered everything (apart from the 1080Ti). Even if P3D does change, it will still work really well on this system I'm sure - it's not like 4 core performance is suddenly going to be terrible, it just may make use of a few more cores. But it's guesswork anyway so I'm happy with my final choice. Just need to build it once the parts arrive!

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7700k is a smart choice.  It's exactly the one I made for my Flight Sim box a couple weeks ago, even knowing the Ryzen launch was imminent. ;)

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