Core Blimey!

[Samuri]

Ok this one is for the real techies here...

Peeps, got an interesting question here: running a quad core QX6700 and found an option on my motherboard, Gigabyte DS4 to limit CPU ID to 3 to stay compatible with older OS's, or something similar. Anyway, upon setting that option on, I have found out that in XP or Vista for that matter shows my cpu to have only 2 cores instead of 4, effectively turning off 2 cores. I ran SiSoft to confirm and it benches the same as the dual core E6700.

On device manager - it only shows 2 processors, so are only 2 real cores being used or is this virtual 2 cores or 1?

Power consumption is it less because of it or the same?

 

[Stelly]

Have you updated your BIOS?

You have to update it to get Kentsfield to work on the DS4

Stelly

 

[Samuri]

Yes, latest bios - and putting that setting is not a problem - just wanna know what i was asking before technically speaking :

1. On device manager - it only shows 2 processors, so are only 2 real cores being used or is this virtual 2 cores or 1?

2. Power consumption is it less because of it or the same?

 

[Bizarre]

Yes, latest bios - and putting that setting is not a problem - just wanna know what i was asking before technically speaking :

1. On device manager - it only shows 2 processors, so are only 2 real cores being used or is this virtual 2 cores or 1?

Conroe architecture can't simulate multi cores, hence you still have 2 'real' cores at work. Although Intel are reintroducing hyperthreading into their new Nehalem core which is scheduled for a 2008 release.

2. Power consumption is it less because of it or the same?

I'd imagine less, as (obviously) 2 cores consume less power than 4.

 

[Samuri]

I think my question isn't so clear - so I will try to reiterate in a different way...

Does changing the settings on the motherboard : SET CPU ID LIMIT TO 3

really turn off 2 of the 4 cores?

 

[Duff-Man]

I think my question isn't so clear - so I will try to reiterate in a different way...

Does changing the settings on the motherboard : SET CPU ID LIMIT TO 3

really turn off 2 of the 4 cores?

I'm not sure...

CPU ID = 3 should represent 4 cores, as core numbering starts from 0.

However, if everything works as expected when you disable this option I would imagine the answer is yes - the motherboard simply 'ignores' the last two cores.

 

[Darg]

If enabling the option disables two of your cores then why do it? Simply disable the option and have all 4 cores running. Seems quite obvious to me, you did the testing yourself to answer your own question.

 

[Samuri]

lol @ darg

There are sometimes reasons to turn off quad core when running certain progs that perform better without 4 cores.

Also, when the computer is running purely as a server without local cpu usage, there might be a way to manipulate it to auto-turn off 2 cores - or I could do that manually when i know i will be away for a long while, meaning less power usage etc etc....

And what I find funny is when people instead of being able to answer the questions at hand, always ask "why do it, or don't bother". Its always helpful if people would consider that we all use computers in different ways and for different things.

Oh and duffman, thanks for your response much appreciated