8 cores? noob question

Today I was trying to OC my cpu a tad for extra power for 5 boxing. Long story short i failed at OCing.. my PC would freeze no matter what i tired ( using guides ) So i set things back to default ( an option you get when you fail as you reboot)

So heres the question. When i made teams in ISboxer in the past, and set up each slot with hotkeys and what cores i wanted to assign, I always had 4 cores showing. Now i am showing 8? I think I remember, back when i built this PC, i did something I was recommended to do that shut off threading? Not even sure I'm saying it right. I guess my question is why am i showing 8 cores on a quad core cpu? And why was i only showing 4 before?

The 4 extra cores would be virtual hyperthreading cores. 4 physical cores, and one more virtual one per physical.
I don't see any reason why you would want to disable that in BIOS.

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Originally Posted by Fef

The 4 extra cores would be virtual hyperthreading cores. 4 physical cores, and one more virtual one per physical.
I don't see any reason why you would want to disable that in BIOS.

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Yea, i cant remember why i was told to, i just remember it had something to do with me trying to get 5 copies of WoW working right at the time. I was using Keyclone at the time and i would log in,, turn every setting to low and still lag like crazy. When i disabled hyperthreading I "think" that helped.. not sure though.

Does Hyperthreading help with multiboxing?

I set ISboxer to use only physical cores on my system. Every client is allowed to use every physical core. The hyperthreaded virtual cores are therefore not activated in ISboxer, but they remain active for the rest of system and can be used by other processes than WoW clients. That must globally help multi-boxing performances, I would think.

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Originally Posted by Fef

I set ISboxer to use only physical cores on my system. Every client is allowed to use every physical core. The hyperthreaded virtual cores are therefore not activated in ISboxer, but they remain active for the rest of system and can be used by other processes than WoW clients. That must globally help multi-boxing performances, I would think.

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Sounds good, I'm guessing every other core listed is virtual? so 1-3-5-7 are the physical ones?

Hyper-threading can hinder gaming... might want to do some tests with and without it. Everyone's system
is a little different.

The primary problem with 4(8) core systems is that most folks don't realize there are only 4 physical cores. So what would happen is people would assign one game to cores 0/1, one to 2/3, one to 4/5, one to 6/7. This is incorrect as it only assigns one physical core to each game. So what you want to do with the 4(8) core i7 quads is assign games to two physical cores per game ONLY (for WoW, which only utilizes two cores per process). Leave the virtual cores for your OS to dynamically assign/load-balance.

See this thread for the layout of which cores are virtual and which aren't.
http://www.vindicatum.com/forums/viewtopic.php?id=206

Short version of an i7 affinity mask (in decimal):
1(1v)2(2v)3(3v)4(4v) <-- cores
1(2)4(8)16(32)64(128) <-- mask values
1+4+16+64 = 85 (decimal; 0x55 hex)
good default affinity mask setting for WoW is 84 per this blue confirmation

So, unless something has changed, for multiboxing most games like WoW you want two physical cores per game instance distributed as evenly as possible across your game instances.

Example i7 (4+4 hyperthreaded) config:
Game 1 and/or 3 = 1+4 = 5
Game 2 and/or 4 = 16+64 = 80

Example Q6600 (4+0 non-hyperthreaded) config:
Game 1 and/or 3 = 1+2 = 3
Game 2 and/or 4 = 4+8 = 12

Personally, having all physical cores on all game clients gave me the best performance.

Assigning the logical cores (hyperthreading) was a very slight loss in performance.
As was assigning physical cores to specific windows, rather than having all cores on all games and letting windows manage where the power goes.

I've heard the reverse from some people.
Pretty much run Perfmon for a few hours of typical gaming with each option.
The configuration that pushes the computer the least, is probably the optimal settings.
Not a whole lot of difference for me, either way really.

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Originally Posted by Ualaa

Personally, having all physical cores on all game clients gave me the best performance.

Assigning the logical cores (hyperthreading) was a very slight loss in performance.
As was assigning physical cores to specific windows, rather than having all cores on all games and letting windows manage where the power goes.

I've heard the reverse from some people.
Pretty much run Perfmon for a few hours of typical gaming with each option.
The configuration that pushes the computer the least, is probably the optimal settings.
Not a whole lot of difference for me, either way really.

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Yeah, there are a host of things that affect how multithreaded apps perform on multi-core systems. The most important, of course, is how the application is optimized. ;) Knowledge and testing are really the only two things that can provide a definitive answer.