Please help me decide between I5 6600k and I7 6700k

[czglory]

I have spent countless hours debating between these for my upcoming build, and I am no closer to a solution. I am selling my current rig with an I7 3770k which I did not end up overclocking, I did not get along with my current motherboard. I use my computer mostly for what would be "general producitivty" things. I tend to use photoshop sometimes (rarely), but I do have time-sensitive calculators that crunch with the processor in real time. I plan on going without a GPU until Pascal, and fit the build into a small form factor case (raven rvz02 or silverstone core v1). I do some gaming, but it is not a priority.

Is there any way I can scientifically determine the value of the 6700k? Or rule it out? The savings would help, but I spend nearly all day on the computer, so if I am wasting either time or money with either choice, it is beneficial for me to determine that.

I7 6700k : $375
I7 6700: $342
I5 6600k : $266
I5 6600: $246

These are what I am considering, leaning towards I7 6700k. Any thoughts/advice/etc would be amazing!

 

[ThatBuzzkiller]

If you can just tell us what applications you're using and show some benchmarks it would be really helpful.

 

[frozentundra123456]

I would go with the 6700k. High stock clocks plus hyperthreading. Doesnt cost that much more relative to the cost of an entire system, especially considering you will probably keep the systems for several years. Also, I dont think I would want to go back from an 8 thread 3770k to a 4 thread Skylake.

In fact, depending on how well threaded your apps are, you might want to consider the HEDT platform.

 

[czglory]

If you can just tell us what applications you're using and show some benchmarks it would be really helpful.

they are rather obscure programs, holdem resources calculator, a java based nash-equilibrium calculator, and a much more intensive program called piosolver which does similar work but is much more complex. Its also difficult to explain. I use a version of it that "uses up to four cpu cores". Its possible in the next 6 months I will be using their version which is more advanced and "uses up to 12 CPU cores / 12 hardware threads)", but I will not likely use any more complex calculator than that on this build. (Requires 64 GB ram, I7 5820k+ recommended).

Most of the calculations I do run for less than 30 seconds, but its important they are done as quickly as possible. The "uses up to four cores" version seems like perhaps it would not benefit from an i7 over an i5, but the "uses up to 12 cores" would. Is that correct?

tundra; I definitely agree and this is why I am leaning towards the i7 6700k by default. I may *not* keep the system for a few years however, if I do need to upgrade I would infact need this HEDT platform/I7 5930k/64 GB ram, etc. For now, its possible that if my asumptions are correct ("Uses up to four threads", ) I may be unnecessarily spending money on an I7, but I want to be postiive first.

I need small factor as I am going to be traveling and can't get a comparable laptop for the same price. I thank you for the thoughtful reply.

 

[coercitiv]

tundra; I definitely agree and this is why I am leaning towards the i7 6700k by default. I may *not* keep the system for a few years however, if I do need to upgrade I would infact need this HEDT platform/I7 5930k/64 GB ram, etc. For now, its possible that if my asumptions are correct ("Uses up to four threads", ) I may be unnecessarily spending money on an I7, but I want to be postiive first.

Taking into consideration you are willing to upgrade once your software can efficiently use a more powerful system, all you need to do is check whether your current calculators benefit from Hyper-Threading.

With that in mind, my suggestion is to use your current system for a benchmark:

• write down how much time each calculator takes on your current system (exact value, average, minimum.. whatever fits the variance in your software)
• disable HT from BIOS and see how this affects your time results.

If you can observe clear gains (20%+) in any of the calculators while Hyper-Threading is enabled then you'll have a clear indication 6700k is a good option for your. However, if results are more or less the same, then the only benefit a 6700k might bring will be in the future, with new software. There may even be an unlikely case where results get a bit better with HT off.

I'm not taking into account the frequency difference between 6600k and 6700k since they both overclock, and the difference of 5% in maximum clocks can go either way.

 

[czglory]

Taking into consideration you are willing to upgrade once your software can efficiently use a more powerful system, all you need to do is check whether your current calculators benefit from Hyper-Threading.

With that in mind, my suggestion is to use your current system for a benchmark:

• write down how much time each calculator takes on your current system (exact value, average, minimum.. whatever fits the variance in your software)
• disable HT from BIOS and see how this affects your time results.

If you can observe clear gains (20%+) in any of the calculators while Hyper-Threading is enabled then you'll have a clear indication 6700k is a good option for your. However, if results are more or less the same, then the only benefit a 6700k might bring will be in the future, with new software. There may even be an unlikely case where results get a bit better with HT off.

I'm not taking into account the frequency difference between 6600k and 6700k since they both overclock, and the difference of 5% in maximum clocks can go either way.

excellent idea, just what I was looking for!

 

[ThatBuzzkiller]

I would pick the i7 6700K at this point when there's a lot of uncertainty in the performance characteristics in the programs you use ...

How cache friendly, memory bandwidth intensive, or even compute limited it is remains a mystery ...

Maybe you can test out the affect that clock speeds have by underclocking your processor ...

 

[ShintaiDK]

6700K. +500Mhz stock, +2MB cache and +HT.

Remember you need a 3rd party cooler with the K models.

 

[christian1990]

go with the i7

 

[lehtv]

go with the i7

Helpful comments like this is why the Anandtech community is great. Why bother with long-winded trains of thought and laboriously constructed and well supported arguments, when all you really need is a sentence of four words lacking any punctuation? :thumbsup:

 

[Yuriman]

It's possible that your 4-thread calculator might cause a 4-thread CPU to give a less-than-perfect desktop experience while it's running in the background, so from that perspective, an i7 is a safer bet.

The 6700 is lower clocked than the 6700K, but is cheaper and comes with an "adequate" cooler. You also don't necessarily need to invest in a Z170-based board for it. All things considered, it's probably not much more expensive than a 6600K.

 

[stockwiz]

i7 for the win.

 

[czglory]

thanks guys I did some 'benchmarks' with one of the calculators, the hyper threading helped in every test run but not by a large margin, times were:
hyperthreading enabled:
21:06
19:06
18:49
18:14
hyperthreading disabled
23:29
19:37
19:54
20:48
not a large difference, but some. This was the unmarked calculator not the four thread one, I am not sure how to measure this one. The experience while running is really bad in both cases, lag on any action. The CPU useage was steadily at 94%-100% during the crunching and the computer is hardly useable during that time. using min 7261 mb ram max 10,009; 8815 / 13315 pagefile.

The results were closer than I had suspected but do show the processor is very heavily taxed at least. I will try to run more numbers and see with the other calculators.

 

[coercitiv]

using min 7261 mb ram max 10,009; 8815 / 13315 pagefile.

Since there is a good chance your calculators may be at least somewhat sensitive to memory speed, keep that in mind as well as you plan your purchase.

DDR4 kits vary in speed from 2133 to 3200+, with 2133 CL15 being considered inferior to recent DDR3 kits (latency wise). Without paying much extra you should be able to buy something faster. Standard voltage for DDR4 is 1.2V, but 1.35 is also ok. Don't go overboard with the memory budget though. (aim for 2800+, or 2400-2666 at CL 12-13, but anything above 2400 with a good price will be better than baseline 2133)

 

[ed21x]

thanks guys I did some 'benchmarks' with one of the calculators, the hyper threading helped in every test run but not by a large margin, times were:
hyperthreading enabled:
21:06
19:06
18:49
18:14
hyperthreading disabled
23:29
19:37
19:54
20:48
not a large difference, but some. This was the unmarked calculator not the four thread one, I am not sure how to measure this one. The experience while running is really bad in both cases, lag on any action. The CPU useage was steadily at 94%-100% during the crunching and the computer is hardly useable during that time. using min 7261 mb ram max 10,009; 8815 / 13315 pagefile.

The results were closer than I had suspected but do show the processor is very heavily taxed at least. I will try to run more numbers and see with the other calculators.

10% hyperthreading advantage + 10% higher clock advantage + potentially higher overclock

you're looking at around a 20% gain in performance going from i5 to i7. definitely worth it.

 

[czglory]

Ok, I will go with the I7 now for sure. Just need to choose between the I7 6700 / I7 6700k. Mostly looking at the motherboards and cases to help decide this.. if I go a very small case I will likely get 6700 and if I get one with sufficient space and cooling abilities (can support cPU cooler) I will go for the 6700k.

Since there is a good chance your calculators may be at least somewhat sensitive to memory speed, keep that in mind as well as you plan your purchase.

DDR4 kits vary in speed from 2133 to 3200+, with 2133 CL15 being considered inferior to recent DDR3 kits (latency wise). Without paying much extra you should be able to buy something faster. Standard voltage for DDR4 is 1.2V, but 1.35 is also ok. Don't go overboard with the memory budget though. (aim for 2800+, or 2400-2666 at CL 12-13, but anything above 2400 with a good price will be better than baseline 2133)

I do feel like memory is an issue with these calculators, I appreciate this!

considering these choices from corsair vengeance line, g.skill is very slightly more expensive, any thoughts on which is the best buy? thinking of the 3000 or 2400.

Corsair vengeance LPX:

2133 MHz (CAS 13) = $105.40

2400 MHz (CAS 14)= $109.15

2666 MHz (CAS 16) = $122.27

3000 MHz (CAS 15)= $137.44

3200 MHz (CAS 16) =$150.40

 

[ThatBuzzkiller]

Ok, I will go with the I7 now for sure. Just need to choose between the I7 6700 / I7 6700k. Mostly looking at the motherboards and cases to help decide this.. if I go a very small case I will likely get 6700 and if I get one with sufficient space and cooling abilities (can support cPU cooler) I will go for the 6700k.


I do feel like memory is an issue with these calculators, I appreciate this!

considering these choices from corsair vengeance line, g.skill is very slightly more expensive, any thoughts on which is the best buy? thinking of the 3000 or 2400.

Corsair vengeance LPX:

2133 MHz (CAS 13) = $105.40

2400 MHz (CAS 14)= $109.15

2666 MHz (CAS 16) = $122.27

3000 MHz (CAS 15)= $137.44

3200 MHz (CAS 16) =$150.40

If memory bandwidth is a concern the least you could do is attempt to benchmark your programs at different memory clock speeds ...

An i7 6700K seems like a lock since your getting 17% higher stock clocks with a 10% increase in price ...

 

[SPBHM]

unless you are going with a very cheap motherboard I would consider the 5820K if you are considering the 6700K.

 

[coercitiv]

10% higher clock advantage + potentially higher overclock

I wouldn't take clocks into the equation, he is bound to overclock and 6600K is perfectly capable of achieving high clocks. If 6700K brings sensible gains through HT and also promises better scaling for future software, concentrate on that.

considering these choices from corsair vengeance line, g.skill is very slightly more expensive, any thoughts on which is the best buy? thinking of the 3000 or 2400.

If I knew for sure the software has excellent scaling with memory speed I would go for 3000, otherwise the 2400 option seems reasonable, especially if the timings are for 1.2V. I guess it also depends on your final budget, maybe make the choice when the rest of the components are locked in?

 

[czglory]

unless you are going with a very cheap motherboard I would consider the 5820K if you are considering the 6700K.

I would love the 5820k, but it is much more expensive than the 6700k (~$50), it does not support mini ITX which is the form factor I want, and the x99 motherboards here are extremely expensive, the cheapest being more than $250.

I wouldn't take clocks into the equation, he is bound to overclock and 6600K is perfectly capable of achieving high clocks. If 6700K brings sensible gains through HT and also promises better scaling for future software, concentrate on that.


If I knew for sure the software has excellent scaling with memory speed I would go for 3000, otherwise the 2400 option seems reasonable, especially if the timings are for 1.2V. I guess it also depends on your final budget, maybe make the choice when the rest of the components are locked in?

Thank you. The 3000 mhz is 1.35 v and the I will probably 2400 mhz is 1.2 v. I honestly do not know anything about the voltages in ram so I will have to look into this, but the difference seems relatively minor compared to other things like the processor. I will likely spring for the more expensive memory even though I am on a budget.

 

[myocardia]

The 6700 is lower clocked than the 6700K, but is cheaper and comes with an "adequate" cooler. You also don't necessarily need to invest in a Z170-based board for it.

Unless you want to use faster system RAM than 2,133. Z170 is the only current Intel chipset that allows faster than 2,133. Even H170 doesn't have the ability.

 

[Burpo]

I7 5820K @ $374

http://www.superbiiz.com/detail.php...5G9qxKE6F5RiAAGZoNHM7Y_mcnuxtYsq1HRoCPqvw_wcB

Motherboards are generally more expensive tho..

 

[czglory]

I7 5820K @ $374

http://www.superbiiz.com/detail.php...5G9qxKE6F5RiAAGZoNHM7Y_mcnuxtYsq1HRoCPqvw_wcB

Motherboards are generally more expensive tho..

$430 here, I would love to snap that up, but I do want a small form factor case. Definitely my favorite processor, though.

 

[cytg111]

i7, cause the chip will last you a decade and 10 years of performance delta i5 vs i7 for 100$ is a nobrainer.

 

[Yuriman]

$430 here, I would love to snap that up, but I do want a small form factor case. Definitely my favorite processor, though.

Check this out:

http://www.newegg.com/Product/Product.aspx?Item=N82E16813157588

Anandtech did a review on it a while back. I don't think you can use a normal cooler, but there might be other options. No idea if the included cooler will be reasonably quiet.