[Techno-Kitchen] i5-6400 3.1 Ghz vs. i5-6400 4.5Ghz w/ GTX1060 2Ghz => CPU bottlenecking explored

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SlickR12345

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Jan 9, 2010
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Can't wait for Zen to shake things up in the CPU market, AMD better make this right. I would love me some $180 8-core chip that blows away the competition.

With DX12 many games can utilize unlimited amount of cores. We are seeing the slow death of 4 core processors, they still have life in them, but in one and a half year they will be extremely weak to handle all new games.
 
Mar 10, 2006
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Can't wait for Zen to shake things up in the CPU market, AMD better make this right. I would love me some $180 8-core chip that blows away the competition.

With DX12 many games can utilize unlimited amount of cores. We are seeing the slow death of 4 core processors, they still have life in them, but in one and a half year they will be extremely weak to handle all new games.

Why would AMD sell a competitive 8 core chip for $180?
 

RussianSensation

Elite Member
Sep 5, 2003
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Since multithreaing in games has become a trend (and DX11 has become CPU bound with modern high end gpus) nowadays an i7/xeon with HT is required for the best/proper performance in some recent games

That is absolutely true. I regret to this day going with an i5-2500K after owning an i7-860. I didn't make the same mistake again when I finally upgraded to i7-6700K, despite how good i5-6600K looked in most benchmarks online. Over 5 years of ownership, the extra $100 is $20 a year and a peace of mind for higher minimum FPS.

I run my 5930K at 3.7GHz and while a new $1K Kaby Lake core parts would be fun, still seems rather pointless. Besides, why didn't they test @ 3.5GHz for comparison as that is the standard speed of less gimped Intel CPUs. The i5 6400 is a reject CPU anyway.

Don't forget that many Intel CPUs that are rated at 3.7-3.8Ghz for only dual-core Turbo Boost.

i5-6500 is rated at 3.6Ghz boost but with 4 cores loaded, it's only 3.3Ghz actual.

Here is a follow-up test with i5-6400 vs. i5-6500. Identical results. i5-6500 is still a major bottleneck since it's barely faster than a stock i5-6400.
GTX 1060 6Gb @ 2000
i5-6400 (3,1) vs. i5-6500 (3,3)
2*8 GB DDR4
https://www.youtube.com/watch?v=ipCH_qPvDe8

Yeah, stock i5-6400 level of performance (~i5-4460) was bottlenecking ultra details for a while now, like a good year. But still High is ok for 60fps at almost all games.

Soon it will drop to medium and that will mean visual quality has to be sacrificed = trash cpu :p
But Zen is ready, and 6-core mainstream is incoming.

Good thing Z170 BLKC overclocking is still in effect on some boards. It can turn an i5-6400 into a nice CPU at 4.4-4.6Ghz.

I was going to build an i5 6400 build oc it at around 4.5ghz, but found an used i7 4790k build which cost me less and its faster...i will stick to this i7 haswell till coffeelake 6cores comes out...even the i7 6700k is not enough for bf1 if you want very high fps...for example next year 240hz monitors comes out, and the i7 6700k cant give you more then 180fps even if you game on low settings..

There is no GPU in the world that's coming out in 2017 that will play AAA games at 240Hz at 1080p without turning settings down.

The issue with an i7-4790K is older Z170 boards, most of which lack PCIe 3.0 x4 M.2 slots, and DDR3 memory that cant be reused for Ice Lake or whatever. I would have just gotten an i7-6700 non-K and overclocked it if the $ was tight for an i7-6700K. The $ spent on DDR4 alone is the same as "savings" since DDR4-3000 memory should still be good for the next 3-4 years.

So, after ~3 years of service, the 4670K still manages to feed a modern graphics card in a seemingly CPU demanding AAA title, yet we tend to recommend against buying 4C/4T even with clear signs that 2017 and most importantly 2018 will bring about a uniform increase in thread count on both Intel and AMD CPUs, making the i7 of today the i5 of tomorrow: that total cost of ownership will be all over the place.

Why would it be all over the place? We can estimate it. Current Newegg prices: i5-6600K costs $219 and i7-6700K costs $299.

Let's say I sell both CPUs at 30-70% (simulated scale) of their resale value in 5 years from now.

70% resale value = $299*0.7 - $219*0.7 = $56
60% resale value = $299*0.6 - $219*0.6 = $48
50% resale value = $299*0.5 - $219*0.5 = $40
40% resale value = $299*0.4 - $219*0.4 = $32
30% resale value = $299*0.4 - $219*0.4 = $24

Without reselling the i7-6700K, the total difference is $80 and it varies between $24-56 assuming 30-70% resale value in 5 years. Using this methodology, an i5 makes no sense to me.

On top of that, the i5 6400 stock clocks are so gimped that even an i3 offers more consistent performance on a GTX 1080 FTW, yet we somehow hear the quad core swansong in budget builds based on GTX 1060.

The difference is an i5 has the potential to overclock and become a solid i5. i3 will become a more consistent bottleneck across various PC genres, especially strategy games (see my charts below in anothe rpost).

There are also plenty of games when an i3 loses badly to the i5 and FX9590. It would be a big waste of $ to buy an i3 and pairing it with GTX1070/1080 level GPUs. i3 is already outdated for these GPUs.


Can't wait to see that i3 7350K overclocked to 4.7Ghz+ in gaming benchmarks, I can already see the hoops.

There is no hoops here because if an i5 user did their research and bought the right Z170 board, they are sitting on a 4.4-4.6Ghz i5-6400 that would smash the $160-170 i3-7350K.

Yes Joe, your i3 is better than i5, but only for the purpose of proving 4C/4T is no longer enough for gaming, otherwise i3 sucks even more. Don't be confused, be enthusiast.

There are plenty of benchmarks and videos online that show an i3 is an even bigger bottleneck than the i5. There will be games that use 2-3 threads at most and are mostly GPU limited. Of course in those titles the i3 will look good.
 
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RussianSensation

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Sep 5, 2003
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Thanks OP. and for those curious how the older i5 2500k@4.5 compares to the i5 6400. I'm sure many folks are still running a sandybridge chip, I know I still have one in a secondary system.

https://www.youtube.com/watch?v=mLW_3aNfZ4M

i5-2500K should be faster since Skylake is only about 25-35% faster in IPC compared to SB. What makes it tricky is that if a game were to use more modern instructions, the Skylake's efficiency in that could easily offset the 4.5Ghz clocks of the i5-2500K. I didn't see the point in upgrading from an i5 to an i5. Given how long CPUs last now, I think the smart buy now is i7-6700K (or obviously i7-7700K) or even i7-6800K.

I would hate to even try to guess the percentage gain going from SandyBridge to Skylake in gaming but I will say the difference can be quite significant under the right circumstances. Take the game Watch Dogs for example My i5 2500k @4.5 would dip all the way into the 30s while my i7 6700k@4.5 never goes below 60. (doesn't matter if hyperthreading is disabled or not)

In the first Watch Dogs, the i7-6700K was 50% faster than a stock i5-2500K.
getgraphimg.php


getgraphimg.php

In strategy gaming genre, an i5 2500K is a completely dog.
getgraphimg.php


getgraphimg.php


getgraphimg.php


XxhXDJKP2x6Z9jPMP7XgjD.png

i got i7 4770k and 3440x1440. I need new card, was thinking of 1070 or wait for vega. Would i be cpu bottlenecked?

You will be more GPU bottlenecked. 3440x1440 is very demanding, even for a GTX1070. Don't expect to run all AAA games at ultra at such a resolution with a 1070. i7 4770K with GTX1070/1080 is a good pairing overall.

Err, Skylake can take advantage of DDR4 - Sandy Bridge cannot, making your graph totally pointless. High speed DDR4 nets a good performance advantage in addition to Skylake's increased IPC.

Real world performance is what counts.

That is true. Since most gamers don't have GPUs much faster than a single Fury X/1070/1080/980Ti, the extra performance gains Skylake has in it with faster DDR4 memory don't show up.

With 980Ti SLI though and i7-6700K @ 4.5Ghz, the gains are there.
Fallout.png


ARMA3.png


Witcher.png
http://www.techspot.com/article/1171-ddr4-4000-mhz-performance/page3.html

Fallout 4 though is a major outlier imo.
 
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tential

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May 13, 2008
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This is painfully obvious you should get an i7 over an i5. If you bought a modern day i5 you're just cheap.

Since the 4770k release, it was i7 or nothing to me. You're just throwing away current and even more future potential if you get an i5.
 
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Concillian

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On top of that, the i5 6400 stock clocks are so gimped that even an i3 offers more consistent performance on a GTX 1080 FTW, yet we somehow hear the quad core swansong in budget builds based on GTX 1060. Can't wait to see that i3 7350K overclocked to 4.7Ghz+ in gaming benchmarks, I can already see the hoops.

Xd1Y8IP.png


Yes Joe, your i3 is better than i5, but only for the purpose of proving 4C/4T is no longer enough for gaming, otherwise i3 sucks even more. Don't be confused, be enthusiast.

You're calling things "gimped" and "not enough for gaming" that are 0.1% of frames lower than 70 FPS?!?

Wat?

In what world is 100+ FPS average and minimums in the 60s inadequate? Yeah, that 4C/4T sure is struggling at only 96 FPS minimums...

The writing is on the wall guys... soon developers are going to write games that only play well on $600+ CPUs so they can only sell a dozen or two copies. Uh, no.
 

coercitiv

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Jan 24, 2014
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You're calling things "gimped" and "not enough for gaming" that are 0.1% of frames lower than 70 FPS?!?
Read my post again, I'm being as sarcastic as one can possibly be to still maintain a constructive conversation. The i5 6400 is the lowest clocked quad in Intel's 65W lineup, and it shows this weakness even in BF1 when a higher clocked i3 offers more consistent performance. This anomaly also shows that even a well threaded game like BF1 (see HEDT CPU on top due to moar cores) will still scale nicely with frequency.

Don't forget that many Intel CPUs that are rated at 3.7-3.8Ghz for only dual-core Turbo Boost.
Indeed, let's pretend people can't set all core turbo to be equal with max turbo on most boards. How does Asus call their option? Multi Core Enhancement? Sounds promising.

It wasn't long ago the OP was whole heartedly recommending buying a less expensive chipset + i7 6700 for people who wanted to optimize their gaming budget, the rationale being extra threads would not only prevent unwanted performance dips but also offer better overall performance than even overclocked i5 6600K. Now we have a thread that on one side says quads are dying but on the other side preaches buying the "right Z170 board" and overclocking a 4C/4T i5 using a modded BIOS. So lower the price bar a bit more and those performance dips are no longer that important.

Why would it be all over the place? We can estimate it. Current Newegg prices: i5-6600K costs $219 and i7-6700K costs $299.

Let's say I sell both CPUs at 30-70% (simulated scale) of their resale value in 5 years from now.
The OP simply can't make up his mind - quad cores are dying but he would plan to keep a quad core for 5 years from now.

RussianSensation, I have all the respect for your very well documented posts, just like many others I consider your "mini articles" to be worthy of an online publication of your own, but just like you were blind sided back then with the i5 2500K you are now oblivious to the changes coming in the next 2 years, if not sooner.

If the quad core era is at an end, then recommend against buying quads altogether as a long term investment. Be consistent.
 

IllogicalGlory

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Mar 8, 2013
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I think that i7s are starting to take the spot, relative to i5s, that i5s held relative to i3s during the 2011-2014, what could be called the "Sandy Bridge era". In many cases, the i3 performs identically to i5s and i7s, but there were enough use situations/games where the 2 additional physical cores helped to be worth the extra price and made i5s the go to gamer GPU. I think we're getting to a similar point with i7s in modern games; the gap between i5s and i3s has grown since then as well. Perhaps i3s today are closer to the position Pentiums held back in that era. Pentiums are no longer viable if you want comfortable performance in current-gen games.

In short, I think we're reaching the point where i7s can be worth the extra $100-$120, but that's not necessarily equivalent to the death of i5s, simply that i7s have finally achieved a level of performance that's actually noticeably different from them.

Sandy Bridge is also starting to lose its venerable position where the incremental improvements have finally resulted in an arch (Skylake) that's a viable upgrade even at the same clock speed; plus that extra performance can actually come in handy in modern games. Again, it's not useless, just as i5s aren't useless, only that there is value in having something newer.
 
Mar 10, 2006
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You're calling things "gimped" and "not enough for gaming" that are 0.1% of frames lower than 70 FPS?!?

Wat?

In what world is 100+ FPS average and minimums in the 60s inadequate? Yeah, that 4C/4T sure is struggling at only 96 FPS minimums...

The writing is on the wall guys... soon developers are going to write games that only play well on $600+ CPUs so they can only sell a dozen or two copies. Uh, no.

High refresh rate monitors.
 
Mar 10, 2006
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BF1 is one of the onyl games where a Hex core can keep up with the higher frequency/IPC Skylake. 99% of other games all perform better on a 6700K (which easily clock to 4.6/4.7Ghz on air).

Kabylake will further increase this gap. I expect i7 quads will still be the best gaming CPU's until 2020 or so. By then a large enough % should have coffee lake hex's that game developers are confident enough to spend money multi-threading beyond 4 cores.

Game consoles have 8 cores. I am sure that is reason enough for developers to write code that can take advantage of many cores.
 

DamZe

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May 18, 2016
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Hmm... That's not good news for people who don't want to mess around with overclocking and just buy a CPU/MOBO/RAM combo and plug in the best GPU they can buy. Especially when Intel thinks that 4+Ghz is a premium you need to pay for and locking down overclocking for only their K-SKUs. We need Zen to shake things up a bit, if AMD can deliver on the 4c/8t OC-all-you-want-relatively-budget-friendly-Zen-CPU, Intel will finally start to feel the heat.
 
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amenx

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Dec 17, 2004
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Great thread..... for 1080p owners. Now if someone would be industrious enough to re-submit all this info done on 1440p and over would be appreciated.
 

dogen1

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Oct 14, 2014
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No just 1. It previously had 2 cores dedicated to the OS, but since the OS is lighterweight than the Xbox one OS, they can get away with only 1 dedicated core.

Well, games can use 6 and timeslices of the 7th.

But yeah, I'm sure any game that wants to be competitive technically will scale to 6-8 at least to some degree.
 

Mercennarius

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Oct 28, 2015
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Bottom line is anyone building a new computer today should not get anything less than a 6 core processor if they want the best performance in newer games.

2 or 3 years from now quad cores will be all but obsolete in the newest and most demanding games released then.
 

Ranulf

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Jul 18, 2001
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Bottom line is anyone building a new computer today should not get anything less than a 6 core processor if they want the best performance in newer games.

2 or 3 years from now quad cores will be all but obsolete in the newest and most demanding games released then.

Whoa... I'm getting flashbacks from 2010 man. Heavy stuff.
 

Mercennarius

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Oct 28, 2015
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Whoa... I'm getting flashbacks from 2010 man. Heavy stuff.

Difference is back then there was no games that utilized more than 4 cores...so it was all early speculation. Today we are seeing more and more games using more cores and the writing is on the wall for quad cores...in a couple years they won't meet minimum spec for games.
 

tential

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May 13, 2008
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Bottom line is anyone building a new computer today should not get anything less than a 6 core processor if they want the best performance in newer games.

2 or 3 years from now quad cores will be all but obsolete in the newest and most demanding games released then.
Anything less than 6 threads... So an i7 or nothing.
Which isn't bad the i7 is an amazing purchase for what you get. An i7 value wise is going to beat out anything you get gpu wise from Nvidia or amd.

What I don't understand is people who buy an i3 and then drop in an i7 later......
You couldn't wait 1 extra paycheck to just get an i7? Seriously?
 

TheELF

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Dec 22, 2012
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Today we are seeing more and more games using more cores
No we are not seeing that,what we are seeing is more and more games where the porting is beeing done in 5-6 month time after the release of the game and the porting on some games never even get's completed.
BF4 took as long as well to get to a somewhat stable performance level and we can expect the same for BF1.
 

TheELF

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Dec 22, 2012
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There have been SEVERAL game releases over the last 12 month's that can utilize 8+ threads....I don't remember any games in 2010 that could do this. So yes, this is the case.
Every game made for the new consoles can easily utilize 8+ threads, often into the dozens of threads,doesn't mean anything,only the handfull that have design flaws have performance issues.