How can I switch off hyperthreading?

[hgm]

I have an Acer PC with an i7-2600 CPU. My device manager says I have 8 CPUs, while I know it is a quad. So apparently HT is on.

I cannot find any way to switch it off, though. How is this generally done? (I have in 7 on this PC.)

[JuLieN]

AFAIK this is done in the BIOS. (And not all of them include such settings.)

[hgm]

I looked in the BIOS, and could not find anything that sounded like it would do this.

[JuLieN]

I looked in the BIOS, and could not find anything that sounded like it would do this.

Then googling on this matter will tell you that there's no way to turn hyper-threading off. BUT, with windows, you can force a program to use only one specified core... Maybe that would do for you?

Read how to do in the first answer on this page:
http://superuser.com/questions/305887/d ... 7-registry

[rbarreira]

Why would you want to disable it? It increases performance, except perhaps for some badly-written programs which try to occupy all existent CPUs regardless of whether it's advantageous to do so.

[Modern Times]

I looked in the BIOS, and could not find anything that sounded like it would do this.

I'd be very surprised if it wasn't there. What model Acer ?

[Cubeman]

I have an Acer PC with an i7-2600 CPU. My device manager says I have 8 CPUs, while I know it is a quad. So apparently HT is on.

I cannot find any way to switch it off, though. How is this generally done? (I have in 7 on this PC.)

(I have in 7 on this PC.) do you mean Windows 7 ?

[hgm]

Oops yes, I meant to type Win 7.

Why would you want to disable it? It increases performance, except perhaps for some badly-written programs which try to occupy all existent CPUs regardless of whether it's advantageous to do so.

I am running 4 matches in parallel to test modifications of my engine. I test each version on two matches. What I typically see is that on match A-B gives a very significant advantage for B (say), like 58% over 100 games, while the other A-B is dead even (like 51-49).

I want to rule out the possibility that this is because A in the first match got to share a core with some (also badly losing) A from a match A-C, while B and C happened to be assigned a core of their own.

@Ray:

The model is Acer Aspire M3970.

[Modern Times]

The model is Acer Aspire M3970.

You could contact Acer support. It may have a very restrictive locked down BIOS and it might not be possible.

[Dirt]

I have an Acer PC with an i7-2600 CPU. My device manager says I have 8 CPUs, while I know it is a quad. So apparently HT is on.

I cannot find any way to switch it off, though. How is this generally done? (I have in 7 on this PC.)

It should be in the BIOS if anywhere. I will say that this is one reason I got an I5.