Is hyper-threading better if you dont need those double cores?

[Baterka]

I factory restarted BIOS today (pardon me... Its called UEFI today right :D) and I realized my Hyper-Threading got disabled and just 6 cores (i7-8700) were recognized in Win10.

 

At this moment I got and idea to ask somewhere if having 12 cores other than 6 when those double cores are still one physical core is actually benefitical for someone who not always using all 6 of them

 

For example when I am indexing inside my developer IDE I really doubt that it using 12 cores to do so. Same with games right?

 

Or Hyper-Threading is really about doubling core count without slowing down the physical core?

Is it 2x performance from single core? 

 

[Princess Luna]

Hyper-threading improves the performance of your cores by around 30% being very crude about it... virtual cores are not the same as physical ones but they help and you should use them.

[JoostinOnline]

They aren't cores, even if Windows calls them that. And I would definitely recommend enabling hyper-threading. Whether it will help depends on the task at hand, but there are very few cases where it will hurt. When it actually helps, it tends to make a big difference.

 

Edit: here's a video explaining it

 

[.Apex.]

7 minutes ago, Baterka said:

I factory restarted BIOS today (pardon me... Its called UEFI today right :D)

It's a UEFI BIOS, so it's still called BIOS.

7 minutes ago, Baterka said:

and I realized my Hyper-Threading got disabled and just 6 cores (i7-8700) were recognized in Win10.

Why would resetting BIOS disable Hyper-Threading? unless I guess it's an OEM board and they're too cautious with Intel's vulnerabilities? it's stupid of them to do that regardless.

 

8 minutes ago, Baterka said:

At this moment I got and idea to ask somewhere if having 12 cores other than 6 when those double cores are still one physical core is actually benefitical for someone who not always using all 6 of them

They're 12 Threads and 6 Cores, each core gets 2 threads and it's always beneficial regardless if you use them or not.

10 minutes ago, Baterka said:

Or Hyper-Threading is really about doubling core count without slowing down the physical core?

Is it 2x performance from single core? 

It doesn't double the performance but since each core gets 2 threads, the physical core gets more to do which utilizes the core to its full extent without leaving parts of the core idling by unoptimized software.

[Fasauceome]

Hyperthreading works by flooding the instruction pipeline of a given core, letting it do multiple things at once. Its performance increase scales with whatever instruction set you're using, so sometimes it's a great improvement and sometimes it's meh, but a hyperthread never acts as effectively as a true core. Either way, disabling hyperthreading just makes it so your CPU can do less work, because your clock speeds won't increase or anything. arguably you could use the reduced heat output for more overclocking, but not in this case with a locked i7

[Guest]

Here I thought SMT/HT was running 2 threads per one clock cycle...... *shrugs" 

Learnt somethin' new today!

Pipeline length comes in stages. I believe the 8700K is 14 stages long. 

The more pipeline stages you have, generally the higher clock frequency can be obtained, but with a decrease in per core IPC.

NetBurst Prescott for example had 31 stages. This is why seeing architecture that old was able to hit 8ghz frequency on extreme cooling.

 

 

 

 

[igormp]

1 hour ago, Baterka said:

I factory restarted BIOS today (pardon me... Its called UEFI today right :D) and I realized my Hyper-Threading got disabled and just 6 cores (i7-8700) were recognized in Win10.

 

At this moment I got and idea to ask somewhere if having 12 cores other than 6 when those double cores are still one physical core is actually benefitical for someone who not always using all 6 of them

 

For example when I am indexing inside my developer IDE I really doubt that it using 12 cores to do so. Same with games right?

 

Or Hyper-Threading is really about doubling core count without slowing down the physical core?

Is it 2x performance from single core? 

 

Unless you're using some specific program that makes proper use of all execution units of a CPU (such as STAR-CCM+), in which case HT might actually decrease your performance, you're better off leaving it on. I can provide up to 30~40% more performance without any downsides for regular tasks.