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Author Topic: Cpu Help For Nubs.  (Read 103 times)

spartan105

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Cpu Help For Nubs.
« on: June 23, 2005, 09:06:00 PM »

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Andy51

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Cpu Help For Nubs.
« Reply #1 on: June 24, 2005, 11:31:00 AM »

There are actually 6 cores inside the CPU of the XBox 360...

Well kind of actually...

You see M.icrosoft had IBM build in a technology called SMT or simultaneous multi-threading...

So SMT is in each core, there are 3 cores...

What does SMT do?

Well if you had a core with SMT built in.. it allows the core to have a "virtual" core which is not as powerful as an actual core but it generally increases performance up to 50 percent.

So six cores...  kind of..
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nj12nets

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« Reply #2 on: June 24, 2005, 04:46:00 PM »

sorta like 4.5 cores. or well the power of 4.5 cores
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blackchild1101

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« Reply #3 on: June 24, 2005, 07:04:00 PM »

QUOTE(Andy51 @ Jun 24 2005, 07:42 PM)
There are actually 6 cores inside the CPU of the XBox 360...
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Andy51

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« Reply #4 on: June 25, 2005, 11:46:00 AM »

Yeah, that's what I meant
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m_hael

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« Reply #5 on: June 26, 2005, 08:54:00 AM »

Wow you people need to read some CPU docs.

What M$ have told you is.

3.2Ghz PPC with 3 cores each with 2 hardware threads & SMT tech.

In Simultaneous Multi Threading ... the two hardware threads have a thread priority assigned to them by the programmer... say we have 4 levels... 0,1,2,3;

0 being MAX ... if thread 0 is set to MAX priority then it runs with ALL the CPU's power and only allows thread 1 to run during delay cycles...

if its set to 1 then it uses 3/4 of the CPU whilst thread 1 gets 1/4... etc... (note this is a major simplification).

The core will always attempt to fill delays in one thread with instructions from another thus the Simultaneous name - two instruction steams running through the same execution pipeline at the same time.


Note - this is information freely available on many websites NOT specific to X360 as SMT is NOT a new thing.. just newly implemented.
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Andy51

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« Reply #6 on: June 26, 2005, 02:07:00 PM »

What you said m_hael

It's not exactly in the article in the OXM, which is written by the people at MAXIMUM PC..

But am I gonna argue with a developer? No..
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m_hael

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« Reply #7 on: June 27, 2005, 11:56:00 PM »

QUOTE({{909}} @ Jun 27 2005, 08:44 PM)
does it really matter? its gonna be fast as fuck
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