AMD Vs Intel

[jdogg707]

Originally posted by: beach2nd1

Originally posted by: Confusednewbie1552
Ok i'm gonna get the 3200+ (newcastle) I hope this is better than the 3.4 ghrz pentium 4 and maybe hopefully the 3.6 ghrz pentium 4. Anyway thanks guys.

How can that be better when the 3200+ is only 2.2 ghz and the pentium 4 is 3.6 ghz? I'm not trying to start any kind of flame war, I just don't understand how it is possible. Anyone care to explain it?

Many many many people have explained this, and all of that wonderful knowledge is within your grasp if you only use the glorious function known as....drum roll please...."Search". If you type in what you want, you will be blessed with the knowledge you wish to receive.

 

[Regs]

The reason why they stress the search feature is because every thread like this turns out to be a 5+ page argument. Why spill blood over history?

 

[JackHawksmoor]

How can that be better when the 3200+ is only 2.2 ghz and the pentium 4 is 3.6 ghz? I'm not trying to start any kind of flame war, I just don't understand how it is possible. Anyone care to explain it?

Because the Athlon 64 does much more work (processes more instructions) for every clock cycle it goes through than the Pentium 4.

Mhz/Ghz speeds mean virtually nothing unless you're comparing otherwise identical processors. Even different versions of the same chip (like the Northwood Pentium 4 versus Prescott Pentium 4) aren't comprable at the same clock speed.

 

[thegorx]

here is an article that might help
Good-Bye, Gigahertz

 

[FishTankX]

How can that be better when the 3200+ is only 2.2 ghz and the pentium 4 is 3.6 ghz? I'm not trying to start any kind of flame war, I just don't understand how it is possible. Anyone care to explain it?

The same way an american muscle car can match or beat a japanese race car at a much lower RPM.

Gigahertz is much like RPM. It's an acurate measure of performance and speed, as long as the engines are identical. But comparing a Dodge viper at such and such a gear and RPM is not apropriate when comparing it to a honda civic.

 

[sharkeeper]

Confusednewbie1552,
Once you reach the Golden Member status, the mods will enable a cool search function for you.

For some, that should be the cool web search.


Cheers!

 

[Ariste]

Originally posted by: beach2nd1

Originally posted by: Confusednewbie1552
Ok i'm gonna get the 3200+ (newcastle) I hope this is better than the 3.4 ghrz pentium 4 and maybe hopefully the 3.6 ghrz pentium 4. Anyway thanks guys.

How can that be better when the 3200+ is only 2.2 ghz and the pentium 4 is 3.6 ghz? I'm not trying to start any kind of flame war, I just don't understand how it is possible. Anyone care to explain it?

Alright, I'll try to explain it.

When most people look at a processor, they look only at the GHz rating to determine how fast the processor is. This is because most people are under the illusion that 3GHz=3 (total work done by processor). This is wrong. The equation should look more like this:

3GHz x (work done per clock cycle)=3.

The difference between AMD processors and Intel processors is that AMD processors, while clocked at lower speeds, do more work per clock cycle. So the real equation for Intel should look like this:

3GHz x (.75)= 2.25 total work done by processor.

AMD, with their shorter processing pipelines, can accomplish more work per clock cycle. They are able to keep the "work" portion of the equation at 1.

3GHz x (1)=3.

So, using the numbers I basically pulled out of nowhere, an AMD processor clocked at 2.25GHz can accomplish the same amount of work as an Intel processor clocked at 3GHz. The real numbers for the Intel work per clock cycle are probably even lower than .75, so that gives AMD an even bigger advantage for each MHz they can add.

That is more or less the reason that AMD is able to keep up with Intel even though they have processors with much lower clock speeds.

Hope that helps,

 

[JackHawksmoor]

I'm semi-pulling this out of my...uh, you know where, but I *THINK* I remember reading a tech article that the Pentium 4 did something like 1.8 instructions per clock cycle while the Athlon 64 did close to 3 instructions per clock cycle.

May be really off, I can't remember, but it's like Ariste said basically that you've got the clock speed multiplied by how much how many instructions are actually being completed in a clock cycle that determines performance.

And of course it can vary depending on what's being processed. The Pentium 4 also has a REAAAAAAAALLY long pipeline (how many stages an instruction has to pass through to be completed), and if that pipeline isn't kept full all the time, its performance suffers. That's probably why the Pentium 4 does pretty well with video encoding (it's predictible) and does poorly at stuff like games and general office/internet performance where there's a lot of branching.

 

[Ariste]

Originally posted by: JackHawksmoor
I'm semi-pulling this out of my...uh, you know where, but I *THINK* I remember reading a tech article that the Pentium 4 did something like 1.8 instructions per clock cycle while the Athlon 64 did close to 3 instructions per clock cycle.

May be really off, I can't remember, but it's like Ariste said basically that you've got the clock speed multiplied by how much how many instructions are actually being completed in a clock cycle that determines performance.

And of course it can vary depending on what's being processed. The Pentium 4 also has a REAAAAAAAALLY long pipeline (how many stages an instruction has to pass through to be completed), and if that pipeline isn't kept full all the time, its performance suffers. That's probably why the Pentium 4 does pretty well with video encoding (it's predictible) and does poorly at stuff like games and general office/internet performance where there's a lot of branching.

Exactly.

If you're right about the 3 instructions per clock cycle for AMD and 1.8 instructions per clock cycle, then the number to put in the equation would be .6.

3GHz x .6 IPC (instructions per cycle)= 1.8.

So a 3GHz Intel processor is comparable to a 1.8 GHz AMD processor, depending on what applications you are running.

JackHawksmoor is also correct about the video encoding etc. Pentiums are better than Athlon 64's at video encoding due to the longer pipeline, but that same longer pipeline also hurts performance in branching applications like games and office/internet performance. If you want a processor for encoding, go for a Pentium 4. If you want one for gaming and general computer stuff, go with an AMD.