overclocking 5820K Disabling cores for better performance

[jwakeford]

Hi, 

I am planing on a new build for this summer, I will be using my PC almost exclusively for gaming. 

At first I thought about going for a 6700K but as I got more informed about the grand scheme of things in the tech world I got to the conclusion that the right path was the 5820K : 

- Direct X12, Vulcan and future game optimizations all point towards a better spreading of the work load throughout the CPU cores, giving multi-core performance a go against single core performance. 
- 5820K when overclocked almost matches an overclocked 6700K. 
- The 5820K has a better value in Price/performance overall. 
- And finally, the point I would like to confirm :  
          You can disable two cores on the 5820K, preferably cherry picking the two worse performing core, and therefore increasing the overall remaining silicon quality. 
           This makes the 4 core 5820K more stable, and easier to cool down as less cores produce less heat. 
All this should result in a quite significant advantage for the 5820K over the 6700K when overclocked. 

What do you think ? 
Is it possible ? Advisable to do so? 

Thanks for your input. 

[z97]

Yes you can turn off two cores per bios, I don't necessarily think it's going to be per say more stable... but temps should be a bit lower. All about that silicon lottery.

[ThinkWithPortals]

3 minutes ago, jwakeford said:

 

Why would you intentionally disable 2 of the cores on your six-core chip? They don't produce that much more heat, like 5 degrees tops.

And disabling two cores isn't going to improve single-core performance. At all.

[Godlygamer23]

Silicon quality doesn't increase due to disabling a couple cores. You are just taking the potentially shittier cores out of the overall equation. It might increase stability when overclocking, but it's not guaranteed. 

[jwakeford]

Just now, ThinkWithPortals said:

Why would you intentionally disable 2 of the cores on your six-core chip? They don't produce that much more heat, like 5 degrees tops.

And disabling two cores isn't going to improve single-core performance. At all.

Because disabling the two lowest performing cores will raise my overall remaining core score and overclockability, not to mention the temperature headroom. 

[Moonzy]

a good concept of approaching things

 

but disabling the cores probably wont yield a higher overclock if your processor is kept cool enough in the first place

 

and you can overclock each core independently so disabling them might allow the other cores to run faster but naah... no one would do that `-`

[Godlygamer23]

1 minute ago, jwakeford said:

Because disabling the two lowest performing cores will raise my overall remaining core score[.]

How so?

[RedWulf]

If you are really worried about heat and energy over computational power then yes,

But, thats like buying a mustang and reducing the engine to that of a focus, all the cost and potential but work went into making it weaker but cheaper to operate per second. 

[z97]

1 minute ago, jwakeford said:

Because disabling the two lowest performing cores will raise my overall remaining core score and overclockability, not to mention the temperature headroom. 

You might as well just go with a 6700k at that point unless you need the PCI lanes

[RedWulf]

I think your confusing clockrate as being directly equal to flops or power

 

3.2*4 > 4.0*2 

[jwakeford]

1 minute ago, Godlygamer23 said:

How so?

Because the way I understand it, the overall overclock is based on the weakest core ? If I put my two weakest cores to sleep, my overclock will be based on the four best and make it seem as if I won the silicon lottery on 4 cores 

[Moonzy]

Just now, jwakeford said:

Because the way I understand it, the overall overclock is based on the weakest core ? If I put my two weakest cores to sleep, my overclock will be based on the four best and make it seem as if I won the silicon lottery on 4 cores 

you can tweak the multiplier for each core independently if im not mistaken?

[ThinkWithPortals]

Just now, jwakeford said:

Because the way I understand it, the overall overclock is based on the weakest core ? If I put my two weakest cores to sleep, my overclock will be based on the four best and make it seem as if I won the silicon lottery on 4 cores 

Not... not really. If that were the case, the overclock on the four cores would be better by such a tiny amount that you would have cancelled it out by disabling two whole cores. It just isn't worth it, you're sacrificing a third of your total cores for a boost in overclockability that likely won't even exist or raise single core performance at all.

And the temperature difference between a 4-core 5820K and a 6-core 5820K is going to be very very small.

[Guest]

7 minutes ago, jwakeford said:

Because disabling the two lowest performing cores will raise my overall remaining core score and overclockability, not to mention the temperature headroom. 

You can do individual core overclocking

Disabling 2 cores is literally the stupidest thing you could EVER do 

Remember, if every core is producing 60c the core temp wont go above 60c, 

6 cores at 60c each is an average of 60c

4 cores at 60c is an average of 60c

Disabling cores really will not help you.

[Guest]

I kind of think you're better off going with 6600k exclusively for gaming. I doubt you will bottleneck with that CPU in games for quite a while. Yes games may utilize more cores, but as the reliance on more cores increases so will the standard of single core performance. In other words, the 5820K won't future proof you any more. 

[Godlygamer23]

3 minutes ago, jwakeford said:

Because the way I understand it, the overall overclock is based on the weakest core ? If I put my two weakest cores to sleep, my overclock will be based on the four best and make it seem as if I won the silicon lottery on 4 cores 

You can technically overclock individual cores, though the benefit of that is debatable. Here's my question for you: How do you know which cores are the worst? You can't pick and choose what cores you want to disable I don't think. 

[DXMember]

3 minutes ago, Moonzy said:

you can tweak the multiplier for each core independently if im not mistaken?

not really you tweak the multiplier for active core count

 

Don't disable cores... but if you do... well then you get more cache than 6700K as well...

[jwakeford]

26 minutes ago, z97 said:

You might as well just go with a 6700k at that point unless you need the PCI lanes

The way I saw it, this tweak would make my 5820K = 6700K performance in gaming as of now, 
while still getting those two extra cores for when games would start requiring more cpu cores with the spreading of DX12 games. 

[jwakeford]

20 minutes ago, Godlygamer23 said:

You can technically overclock individual cores, though the benefit of that is debatable. Here's my question for you: How do you know which cores are the worst? You can't pick and choose what cores you want to disable I don't think. 

I think you know that when overclocking individual cores. And as for picking which to disable I believe it can be done in the UEFI ? but i'm not sure, so if someone could confirm. 

[Godlygamer23]

Just now, jwakeford said:

I think you know that when overclocking individual cores. And as for picking which to disable I believe it can be done in the UEFI ? but i'm not sure, so if someone could confirm. 

You can't choose them I don't think. They just disable.

[TheGamingBarrel]

33 minutes ago, Godlygamer23 said:

Silicon quality doesn't increase due to disabling a couple cores. You are just taking the potentially shittier cores out of the overall equation. It might increase stability when overclocking, but it's not guaranteed. 

Actually, you are wrong. the core running is selected randomly. It makes a massive difference, run SuperPi with 4 Cores at an unstable OC, then do it at 1 Core no HT, Gurantee it will work.

[Godlygamer23]

Just now, TheGamingBarrel said:

Actually, you are wrong. the core running is selected randomly.

I don't know what I stated as wrong.

[TheGamingBarrel]

1 minute ago, Godlygamer23 said:

I don't know what I stated as wrong.

That you take potentially shittier cores out of the equation, and that it might increase oc stability, it isnt a might, it is an is.

[Godlygamer23]

Just now, TheGamingBarrel said:

That you take potentially shittier cores out of the equation, and that it might increase oc stability, it isnt a might, it is an is.

OC stability is dependent on individual cores. If the cores can't sustain the frequency, OC will not be stable regardless. 

[z97]

8 minutes ago, jwakeford said:

The way I saw it, this tweak would make my 5820K = 6700K performance in gaming as of now, 
while still getting those two extra cores for when games would start requiring more cpu cores with the spreading of DX12 games. 

A 5820K has a bit slower IPC than a 6700k. Yes while you can OC, you can almost meet the same performance as a 6700k. Everything depends on the silicon lottery, but disabling 2 cores makes no sense. Buy it cause of the cores and pci lanes, not banking on gaming performance..