i5-2500K vs. i7-4790K for P3D/CV1

[Drizzle 1]

I have a sim rig I only use for Prepar3D V3.3 in VR.  Ever since I built it a few years ago (starting with FSX and moving up through the generations of P3D), I have had excellent luck with my i5-2500K OCed to 4.5GHz.  Even during the past several months while I've been using the DK2, my bottleneck appeared to be more GPU than CPU.

 

But moving up to the CV1 seems to have changed that.  My Core 0 is running pegged to 100% virtually ALL the time I'm flying, and all other cores look like they're living between 85-100% at all times (flying).  The CPU is clearly working harder than it's been used to doing.  Furthermore, I'm experiencing rather frequent blurries, VR drop-outs, and crippling FPS drops at virtually all ORBX airports I've visited so far.  A big change from what I've been experiencing previously.

 

While there likely a multitude of other tweaks and issues to address that will probably result in incremental improvements along the way, I think I need to face trying to resolve what has suddenly appeared to be a significant CPU bottleneck.  Which brings me to a simple question that I'm struggling to find an informed answer to...

 

Are there differences in the underlying architecture between the 2500K and the 4790K that will produce a significantly different result in my experience?  If I'm getting a solid 4.5GHz from the 2500K, and it doesn't look like I'll likely get much if any GHz increase from the 4790K, are there other differences that will produce a noticeably different result in P3D?  So far I'm getting a lot of "yeah, that sounds like a good idea" responses to my question.  But no voices of experience enlightening me as to whether it's a FACT that I'd enjoy better performance.  And if so, why...

 

My bottom line:  If I make this upgrade, it's going to cost me around $600-700 (CPU, MoBo replacement because it's a different socket, and I feel it would be important to upgrade my RAM from 1333 to 2400).  I don't mind doing that if it will result in a NOTICEABLE change in my results.  But I'm not eager to throw that kind of cash out the window for little or no increase in CPU headroom.

 

Thoughts?

[SpiritFlyer 987]

Good Questions Drizzle!

 

I hope you get good answers. I run my 2700K between 4.7 and 4.8gHz with DDR3 RAM.

 

There is no trouble running smoothly with maximum settings with a planeload of add-ons with 2-580GTX video cards in SLI. Although I am getting decent performance (http://www.3dmark.com/3dm11/11324769), I have a mind to stick in a 1080GTX (or 2-1070s in SLI) sooner rather than later.

 

So to paraphrase what Drizzle asks:

 

"Would there be a noticeable real performance improvement in P3D v3.3 with a new rendition of CPU and RAM?"

 

Drizzle, I hope you don't mind me adding to the question mix. ​

 

Kind regards

[Jimm 437]

If I may, one aspect you neglected to mention was how loaded down your sim was/will be with an upgrade?  P3D, FSX by themselves yield great frames and stability (basically all default), but when you start adding AI traffic, weather, scenery, then that's where the playing field gets interesting.  I can say, with experience, that moving from FSX to P3D and all it's incarnations, performance and stability is strong with P3D and that's with ActivSkyNext, ORBX scenery and MyTraffic Pro6, all the while travelling in an Aerosoft A320.  I may not be pushing the boundaries, but for how I like to sim and what I want to experience, that combo has done me well in my laptop rig equipped with a 4790K and a GTX-980M with 32gb of ram, to boot.  I know there are differences between laptop and desktop rigs, but if I may volunteer my rig as a base, then you could turn your attention to $$$$$.  How much are you willing to pay to push your rig to a limit you want to be at?

 

I'm still on P3D v3.2, at the moment, with v3.3 waiting in the wings and I may or may not upgrade, which depends on whether it is necessary for my needs.  I try to take the "don't fix it if it ain't broke" attitude about flight sims now, especially with P3D.  If the sim runs smooth and stable for me, on P3D v3.2, then why should I upgrade, right?  The same thought can be held by you in your situation.  If you feel your older cpu can still cut the mustard, stick with it and save yourself a few clams in the process.

 

Maybe my reply helped, maybe not, but you have some food for thought.  I'm sure you'll get a ton of feedback, lot's of followup questions, but in the end, you wind up taking a step back and assessing what you really want and if it's attainable.

[SpiritFlyer 987]

Here are what seems to be objective comparisons between CPU and GPU platforms and combinations when my FS equipment was tested a couple of days ago. I know that these comparisons are not FS specific so FS platform differences apply.

 

Is this information helpful in these discussions?

 

http://www.futuremark.com/

 

If so, Perhaps running the free futuremark test programs and publishing the results would help us see a somewhat factual comparative analysis.

 

http://www.3dmark.com/3dm11/11324769

 

http://www.futuremark.com/hardware/cpu/Intel+Core+i7-2700K+Processor/review?_ga=1.187359592.1967906754.1466014152

 

Kind regards

[Drizzle 1]

Yashigashi, thanks for sharing your thoughts.  I think most of your questions about my system load are answered in my signature.  And my basic problem is that my 2500K isn't cutting the mustard any longer.  I just need to learn whether investing in its replacement will move my performance marker forward enough to justify the cost...

 

SpiritFlyer, those are good resources -- thanks for posting those.  I wish I was better at reading them -- I'm still finding it hard to discern whether there would be a large gain in the 4790K over the 2500K -- when they are both stretching their legs and operating at the peak of their built-in boost speed -- which I believe is 4.4GHz for both.  Those comparisons SEEM to be posting the performance results for each chip at their native baseline clock-speeds -- 4.0GHz for the 4790K and 3.3GHz for the 2500K.  If that's so, then I don't seem to have a way of accounting for how much of the 4790K's better performance is merely due to the difference in clock-speed (4.0GHz vs. 3.3GHz), and how much of the difference is due to those OTHER factors I'm trying to learn about...

 

I am a modest overclocker, and it looks like I'd get a similar OC speed out of the newer chip as I have from my old one.  If, at those speeds, there wouldn't be a noticeable difference in performance, then there's no point wasting my money.  I think there would/will be a noticeable difference.  But I just feel its necessary to be sure before dropping that kind of coin...

[Jimm 437]

Yashigashi, thanks for sharing your thoughts.  I think most of your questions about my system load are answered in my signature.  And my basic problem is that my 2500K isn't cutting the mustard any longer.  I just need to learn whether investing in its replacement will move my performance marker forward enough to justify the cost...

 

SpiritFlyer, those are good resources -- thanks for posting those.  I wish I was better at reading them -- I'm still finding it hard to discern whether there would be a large gain in the 4790K over the 2500K -- when they are both stretching their legs and operating at the peak of their built-in boost speed -- which I believe is 4.4GHz for both.  Those comparisons SEEM to be posting the performance results for each chip at their native baseline clock-speeds -- 4.0GHz for the 4790K and 3.3GHz for the 2500K.  If that's so, then I don't seem to have a way of accounting for how much of the 4790K's better performance is merely due to the difference in clock-speed (4.0GHz vs. 3.3GHz), and how much of the difference is due to those OTHER factors I'm trying to learn about...

 

I am a modest overclocker, and it looks like I'd get a similar OC speed out of the newer chip as I have from my old one.  If, at those speeds, there wouldn't be a noticeable difference in performance, then there's no point wasting my money.  I think there would/will be a noticeable difference.  But I just feel its necessary to be sure before dropping that kind of coin...

I hear ya, and totally respect the fact that when it comes to upgrades, you want to be sure about a lot.  You'll wind up banging your head against a wall, because you still have a hard time getting all the info you need.

 

My 4790 is overclocked to 4.5ghz and that's what it runs all the time.  No turbo to worry about and well above the base clock speed.  With that and my good card and all SSD setup, I can run P3D rather well.  I hate to say it but your initial question is a loaded one, in that you will get a bunch of people, all telling you different things because it's based on the individual needs of each person.  Combine that with general purpose of the rig, OS, other applications installed outside of flight sim software, whether it is raining and the year you were born, can all enter in to it.  One sound suggestion from someone that swears by the setup may still not be what you want or may function differently.

 

I dipped in to that insanity pit a long time ago and it wasn't worth the stress.  To future-proof a computer is a great idea, but not one easily attained.  If you really feel that unsure that one cpu isn't much better than what you have and money is a big issue, perhaps the best course of action is no further action at all and stick with what you have.

 

I JUST noticed that you have a VR device and I just saw a video not long ago about how to build a $1000 rig, from scratch, to handle VR.  granted, it wasn't set up to use a flight sim application, but it would still make a good base to work from.  Using a pro version of an OS will help (i.e. Win7Pro, Win10Pro) as well.  Everything else looks pretty beefy, so I have to ask why you would feel the need to upgrade?  If it's strictly for the VR, it may be a little premature to do so.  VR is still new and who knows, maybe it all boils down to the application you are using right now to handle it.

[martin-w 3,234]

Are there differences in the underlying architecture between the 2500K and the 4790K that will produce a significantly different result in my experience?  If I'm getting a solid 4.5GHz from the 2500K, and it doesn't look like I'll likely get much if any GHz increase from the 4790K, are there other differences that will produce a noticeably different result in P3D? 

 

 

Well yes, t's a faster architecture. Single core performance in particular is way faster. It's not just about frequency, it's also about IPC. Instructions Per Cycle.

 

http://cpuboss.com/cpus/Intel-Core-i7-4790K-vs-Intel-Core-i5-2500K

 

So if you're considering new MB CPU and RAM... why aren't you considering Skylake? Brand new architecture, lots of new features. M.2, U.2, NFC, USB 3.1, faster ram etc. etc... 

 

6700K will overclock nicely, between 4.6 and 4.8, dependant on the silicone lottery, cooling etc. Everyone on this forum that has upgraded to Skylake has been over the moon with their new systems. I myself have the parts ready to build.

[Drizzle 1]

Thank you Martin!  That was EXACTLY the kind of info I'm looking for!

 

I guess the reason I've not been seriously considering Skylake is that the folks who use their systems exclusively for P3D (as I do) seem to generally feel that there is still an advantage tipping in favor of the 4790K -- specifically for P3D.  But I will explore that a bit more before choosing my path forward.  That single-core performance is very important to us, as P3D still seems to be largely single-core-bound.

[Jimm 437]

Thank you Martin!  That was EXACTLY the kind of info I'm looking for!

 

I guess the reason I've not been seriously considering Skylake is that the folks who use their systems exclusively for P3D (as I do) seem to generally feel that there is still an advantage tipping in favor of the 4790K -- specifically for P3D.  But I will explore that a bit more before choosing my path forward.  That single-core performance is very important to us, as P3D still seems to be largely single-core-bound.

No offense, but his information isn't hard to find.  In fact, before I settled on my rig, I went to CPU Boss and did comparisons of cpus that I found with the rigs i was looking at, which helped me to decide on the 4790.

[Captain Z 32]

Reading through the topic, a lot of good points are made. My 2 cents is that if you will upgrade, you should probably go with the latest chipset. Since you plan on mobo, cpu, and ram....and since the i7-6700k is now around the same price as the 4790k, I would go with the 6700k.

 

Here are some results posted by someone who tested an i5-2500k @ 4.5ghz vs the i7-6700k @ 4.5ghz. Same clock speeds, only major difference being the chipset architecture, and the ram (which does make a difference). No P3D or other sim comparison, but still , some telling numbers.

 

Hope this helps some.

 

http://www.overclock.net/t/1578480/i5-2500k-4-5ghz-vs-6700k-4-5ghz-in-games

 

Edit: I currently use a 2500k at 4.5 as well, and the main thing keeping me from the 6700k is waiting to see how quickly Kaby Lake cpus make an appearance, as they seem to be coming quickly.

[SpiritFlyer 987]

Hi Drizzle,

 

Virtual Reality really (really) is a natural fit for flight simulation. The kind of popularly priced equipment to run it in a sophisticated flight program at sufficient resolution is probably closer than we think. I seriously wonder if now is the time to make a change for change sake.

 

You indicated that you believe your CPU is insufficient, but you are wondering if upgrading from the 2500K to today's state-of-the-art processors would make an appreciable difference to your simulation appreciation experience.

 

Is that right?

 

If so, then I am not so sure. There just is not that much difference, by the numbers, as far as I can see, and what I know about how P3D works. Our processors are similar, and if clocked higher (it won't hurt your 2500K) it will come pretty darn close to what is yet available that impacts P3D v3.3.

 

When new I could run this CPU in the 5.2 range, but since it is 5 years old I keep it below that now. It runs cool and efficient at 4.8-4.9.

 

http://www.3dmark.com/3dm11/11332093

 

Similarly, your 2500 chip can OC much higher and probably fill the performance gap you are looking for. Upgrading or re-pasting an air cooler or adjusting and supplementing what you already have could perhaps be a good solution.

 

When compared for CPU value alone it comes close enough to keep until there is a jump worth jumping to. GPU wise, you are fine! I am considering sticking in a 1080 GTX when the non-reference field opens up. When an equivalent jump comes to CPUs, I will likely port that over and perhaps add another for SLI.

 

But for now I think the Sandy Bridges still compare pretty good, all things considered.

 

Anyway, I will be interested in following your adventures whatever you decide.

 

Kind regards,

[westman 257]

Sometimes the CPU boss single tread mesurements is not at the same freq .

4790k and 4770k at same freq and same mems performs equal.

6700k @ 4.5 with 3200mhz mems is 10-12% faster than a 4790k @ 4.5 with 2400 c9 mems.

Had a 5.4ghz 2700k and a 4.7 ghz 6700k is 10-12% faster in the sim

[martin-w 3,234]

Sometimes the CPU boss single tread mesurements is not at the same freq .

4790k and 4770k at same freq and same mems performs equal.

6700k @ 4.5 with 3200mhz mems is 10-12% faster than a 4790k @ 4.5 with 2400 c9 mems.

Had a 5.4ghz 2700k and a 4.7 ghz 6700k is 10-12% faster in the sim

 

 

Thanks Hasse. Nice to hear from someone who tests these chips on a regular basis and actually knows. There's no substitute for first hand experience.  :smile:

[Drizzle 1]

Very helpful Westman!  Thank you!

 

Are you using the 6700K in P3D?  

[westman 257]

Have one Z170 6700k @5.0 and a X99 5960x @ 4.7 running P3D V3

Prefer the 6700k but this is just my personal option.

Sold my 4790k have it until a was sure that the Skylake was faster.