Dual Core

[builder300544]

Hi,

This is probably a dumb question, but how do you tell if a computer is Dual Core or not.

Preferably without having to open the case.

regards, John

 

[ColPrice2002]

John,

try right clicking "my computer". That will tell you which CPU the system thinks it has.

From that, look up the CPU on Google.

Colin

 

[psycho_aussie]

Alternatively, you can right-click on the taskbar, and select Task Manager (or in XP/Vista, press ctrl+alt+del and select Task Manager). Select the Performance tab, and if the CPU Usage History section shows two boxes, then you have a dual-core. Each box under CPU Usage History is assigned to one physical CPU core.

Chris

 

[builder300544]

Hi,
Thanks for replies.

Right clicking "my computer" got me the answer.

Chris - your suggestion has raised another issue!

I.m lucky enough to have 3 computers and I get the following results.

a. Machine 1 - an Athlon 2400+ shows 1 CPU Usage History Box and in the Device Manager under Computer says ACPI Uniprocessor PC

b. Machine 2 - an Intel Pentium 4 3.2Ghz shows 2 CPU Usage History Boxes and in the Device manager says ACPI Multiprocessor PC. However I,m almost 100% sure it is not a dual core machine.

c. Machine 3 - an Intel Pentium D 2.8Ghz shows 2 CPU Usage History Boxes and says ACPI Multiprocessor PC.

I,m not too computer literate so don,t really understand the above.
Does this mean Machine 2 has some wrong settings??

Regards, John

 

[jfweaver]

As I understand it your #2 and #3 computers both have hyper-threaded processors which act like they have two separate cores but do not (I have one myself in a Dell 4600 purchased 3 years ago). True "dual core" processors have only been produced more recently than the ones you mention.

Jim

 

[builder300544]

Hi,

Jim - I have checked the packaging, and as you quite rightly say Computer 2 has a hyper-threaded processor.

However Computer 3 (according to the packaging) has an Intel Pentium D 820 Dual Core Processor 2.8 GHz with 64 Bit Support.

I,d be very peeved if it is not a true dual core machine, and this is the reason I queried this in the first place.

Regards, John

 

[jfweaver]

You are quite correct John. The Pentium D is a dual core albeit two single cores side-by-side rather than two cores on a single die as with the newer "dual core" technology. Also, they run much hotter.

Jim

 

[sethmcs]

Alternatively, you can right-click on the taskbar, and select Task Manager (or in XP/Vista, press ctrl+alt+del and select Task Manager). Select the Performance tab, and if the CPU Usage History section shows two boxes, then you have a dual-core. Each box under CPU Usage History is assigned to one physical CPU core.

Chris

I have Athlon 64 +3200 and it has two boxes is it a dual core too? If so, whats the big deal?

 

[saintjimmy]

I have Athlon 64 +3200 and it has two boxes is it a dual core too? If so, whats the big deal?

I have an older computer with an AMD Athlon 64 3500+ single core, and it has one box on top of another, and my dual core AMD Athlon 64 X2 6000+ machine has two boxes side by side, both on top of another (bigger) box.

You are probably seeing one box on top of another, right? If so, that is just a single core, like my older single core.

 

[sethmcs]

I have an older computer with an AMD Athlon 64 3500+ single core, and it has one box on top of another, and my dual core AMD Athlon 64 X2 6000+ machine has two boxes side by side, both on top of another (bigger) box.

You are probably seeing one box on top of another, right? If so, that is just a single core, like my older single core.

Nope. Two boxes side by side.

 

[builder300544]

Hi,

Another thought on this subject.

Assuming both my machines were running the same operating system, with the same amount of DDR Ram and the same video card, which would be the more efficient.

I have read where Trainz is not designed for Dual Core, so does this mean my single core 3.2 GHz is better than the dual core 2.8GHz.

Regards, John

 

[psycho_aussie]

The CPU Usage History in Task manager will actually show a Hyperthreaded CPU, with a second "pseudo" core, as two physical cores. So the Pentium 4 showing tow boxes side-by-side is correct.

An Athlon64 3500+ is a single core CPU, so I do not know why you are seeing two boxes under CPU Usage History. That is rather intriguing.

While Trainz will not fully use a dual-core CPU, it will run on one just fine, maybe even better than on a single core CPU, as Windows can allocate resources to the second CPU core, allowing Trainz to run better on the first core.

Chris

 

[builder300544]

An Athlon64 3500+ is a single core CPU, so I do not know why you are seeing two boxes under CPU Usage History. That is rather intriguing.

Hi Chris,

You must have read my post wrong. I did say the Athlon had only one box under CPU Usage history.

Regards, John

 

[nismit]

Hyperthreading was a stepping stone

Posting deleted.

 

[johnwhelan]

The problem with HTT was, that letting two threads loose concurrently, increased the cache contention - everythings else - including cache size - being equal, thereby slowing down memory accesses.

This meant that two threads would more likely than not run slower on a HTT, than on the previous generation CPU, with just multiple instruction issue.

This was not what the HW-guys had intented, but it turned out, that HTT required software to be cache-impact aware, which it isn't, because very few programmers are.

That may be why many game engines force a sequential structure on the critical real-time parts of the application.

It would be intesesting to gather some statistics from trainz users about CPU architecture and CMP performance.

nismit

On most single cpu machines cmp and Trainz runs at 100% cpu, on cpus with hyper theading it runs at roughly 50% cpu. If you look through the forum we did some testing with perfmon to see what was going on.

Cheerio John

 

[psycho_aussie]

Yes, you are correct John. I did read that wrong. Dumb...

Never had much interest in Hyperthreaded CPUs, but that is rather interesting to know, regardless, and the fact that they seem to be able to handle Trainz about as well as a proper dual-core CPU.

Chris