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For the last time, AMD DOES NOT base its PRs on P4s

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dullard

Elite Member
May 21, 2001
26,056
4,708
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Its obviously in comparison to previous XP's based on the same testing suite. If you'd like to take the time to compile a comparison, I'm sure you'd find your answer. I could care less, I spent 3 years at PwC doing due diligence and transaction services in their M&A and Valuation group, so I'm not gonna bother unless you're willing to pay me at my billable rate. I'm sure all the data you're looking for is in a workpaper file in the San Jose office if you really wanna find out. All you have to do though is look at Barton's performance over a 2700+ or 2800+ T-bred in the same tests published in PwC's Opinion Letter on the 3000+, and you'll see where the increased PR comes from.
Suppose AMD made a processor that got all the same scores except Unreal Tournament got 108 fps instead of 105.89 that the 3000+ got. That new chip must be faster. But does that mean it gets a PR of 3001? 3010? 3100? Or what? We don't know. I fully trust their scores are accurate. But how do we get those into a PR?
 

LikeLinus

Lifer
Jul 25, 2001
11,518
670
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Originally posted by: chizow
Originally posted by: dullard
Well, there's also a little piece of paper with a very expensive signature on it from:

PricewaterhouseCoopers

Chiz
No where in that paper does it say where the PR rating came from. It says the fps they got, but not how to convert those into a PR score. That is the one piece of information that AMD has never stated to the public. Are all the tests weighted equally, or are some given more weight? There are tons of similar questions that we don't know the answers to.

If it doesn't say how to get the PR number, then why on earth do they use that paper to verify the PR number? And it certainly cannot be used to know what chip the PR number is currently being based on.

Its obviously in comparison to previous XP's based on the same testing suite. If you'd like to take the time to compile a comparison, I'm sure you'd find your answer. I could care less, I spent 3 years at PwC doing due diligence and transaction services in their M&A and Valuation group, so I'm not gonna bother unless you're willing to pay me at my billable rate. I'm sure all the data you're looking for is in a workpaper file in the San Jose office if you really wanna find out. All you have to do though is look at Barton's performance over a 2700+ or 2800+ T-bred in the same tests published in PwC's Opinion Letter on the 3000+, and you'll see where the increased PR comes from.

Chiz


Can you explain how the laptop CPU's have the same performance rating as the desktops, but perform noticeably less?
 

Mavrick007

Diamond Member
Dec 19, 2001
3,198
0
0
Originally posted by: thorin
For the last time, AMD DOES base its PRs on P4s

Originally posted by: Ilmater
I've said it in forums before, and now an AMD marketing guy has confirmed it. Even though it seems that they base their comparisons on current P4 speeds, they still base their PRs on the same thing they did back when the first XPs came out. Read on:

The Inquirer article
Actually according the AMD page linked in the article it most definately IS based on P4 comparison. And I quote:

"...normalized to P4 3.06Ghz processor with......."

Also I'd like to know how PWC (in this document compared a P4 3.06 vs a 3000+ on Jan01, 2002 as seen on page 4, or at least why they've set the date to 2002 for their tests).

this document @ AMD also shows that the PR rating is based on comparison vs P4(s).

Now you're just talking crazy talk ;)


 

SexyK

Golden Member
Jul 30, 2001
1,343
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Originally posted by: LeeTJ
Originally posted by: SexyK
We all know that already, but it just doesn't matter. Obviously the rating is designed to allow people to compare the XP and the P4 on "equal footing". Anyway, I'll use one of my favorite bits of logic to prove the absurdidty of the PR system.

AMD claims that the PR Rating is based on a comparison to a comparably clocked Thunderbird.
The PR Rating ends up being roughly equivalent to the speed of a comparably clocked Northwood.
Therefore, the Thunderbird and the Northwood perform the exact same number of instructions per clock.

Sooooo, if everyone wants to keep saying that the P4 is a lame architechture for having a "low IPC" then please, please forget trying to defend the PR system. You can't have it both ways, it just doesnt make sense.

OF course it does. The claim by AMD is that the current T-bred and Bartons have higher IPC than comparably clocked P4's. They are also saying that the Thunderbird (an older version of the Athlon processor) has a similar IPC to the Northwoods.

So it is both ways because your talking DIFFERENT AMD processors.


Except that we all know that a Thunderbird 1.5Ghz would pretty much hands down beat out a Northwood at 1.5GHz
rolleye.gif
 

BFG10K

Lifer
Aug 14, 2000
22,709
3,003
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The PR rating might have been based on TBirds once upon a time but today nobody can deny that it's based on P4 clock speed.

Personally I think they should do away with the whole thing because it's starting to trip over itself (the 2800+ beats the 3000+ in a lot of benchmarks).
 

Ilmater

Diamond Member
Jun 13, 2002
7,516
1
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Originally posted by: SexyK
AMD claims that the PR Rating is based on a comparison to a comparably clocked Thunderbird.
The PR Rating ends up being roughly equivalent to the speed of a comparably clocked Northwood.
Therefore, the Thunderbird and the Northwood perform the exact same number of instructions per clock.

Sooooo, if everyone wants to keep saying that the P4 is a lame architechture for having a "low IPC" then please, please forget trying to defend the PR system. You can't have it both ways, it just doesnt make sense.
First off, your logic is terribly flawed. Here's what you stated in general terms (X=MHz):
AMD's PR = T-Bird IPC * X
AMD's PR ~ P4 IPC * X
T-Bird IPC * X = P4 IPC * X

No, you can't do that. It would be correct to say:

T-Bird IPC * X ~ P4 IPC * X

This is, in fact, a true statement. If you remember, clock for clock, the T-Birds were fairly evenly matched to the P4s. That's why the PR system seems to follow the P4 architecture fairly closely.

And don't accuse me of ever saying that the P4 is "inferior" because it gets less IPC. Since we've already established that the P4 and the T-Bird were nearly the same as far as IPC before the Northwood, then I'd say that the two companies took two different approaches to getting more speed: AMD decided on IPC while Intel decided on scalability. While I personally believe that AMD's methods took more work and ingenuity, in the end, we can see who had the best strategy. Intel is clearly having less problems scaling their P4 than AMD is having scaling their AXP.
 

chizow

Diamond Member
Jun 26, 2001
9,537
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Originally posted by: LikeLinus

Can you explain how the laptop CPU's have the same performance rating as the desktops, but perform noticeably less?

Those are limitations of the laptop platform in general, taking into consideration the chipset, onboard gpu, available RAM format, power saving features, slower HDDs, etc. etc. A PR rating is nothing more than a quantification of performance relationships; the CPU will perform at a higher quantified value compared to another laptop. You might as well ask why a P4 2.4 desktop performs better than a P4 2.4 laptop.

Suppose AMD made a processor that got all the same scores except Unreal Tournament got 108 fps instead of 105.89 that the 3000+ got. That new chip must be faster. But does that mean it gets a PR of 3001? 3010? 3100? Or what? We don't know. I fully trust their scores are accurate. But how do we get those into a PR?

That simply wouldn't happen in reality. Remember, a PR rating is only a quantification of relative performance. Once that relationship is identified, it simply scales. Any marginal performance increase/decrease is covered in the standard deviation of error in their testing methodologies. AMD and PwC don't have unlimited resources to simply produce, test, market, and sell chips that perform marginally better; their PR is still limited by logical hardware progression and limitations (which is why we don't see .1 multipliers).

Chiz
 

Ilmater

Diamond Member
Jun 13, 2002
7,516
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Originally posted by: Ctkelly
When AMD started this PR rating it was based on what a T-bird would do. For instance, a 1.47Ghz XP (1700+) would match the performance of a 1.7Ghz T-BIRD.

However, it seems lately that they are more and more based on what they can run against a P4 like others have stated.
AHHHH!!! Are you even READING the link? That's the whole point of this thread. What I'm trying desperately to say is that what you just claimed is not the case. Good Lord!
 

chizow

Diamond Member
Jun 26, 2001
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Originally posted by: LikeLinus
Sounds like their doing a great job :)

Sounds like you're confusing fraud and aggressive accounting methods with a firm's ability to audit.
rolleye.gif


Chiz
 

paralazarguer

Banned
Jun 22, 2002
1,887
0
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AHHHH!!! Are you even READING the link? That's the whole point of this thread. What I'm trying desperately to say is that what you just claimed is not the case. Good Lord!

Most naive man in the world. It doesn't matter what the say. Reasoning people can look at a company's statement and try to understand the motivation for a potentially misleading PR statement. AMD obviously introduced their PR system to combat the diverging design philosophies between AMD's high IPC and Intel's high clocks and the effects that it has on consumers. If you think it would happen if Intel was at the same clock speed as AMD, well.... takes all kinds.

Maybe I'll make that my Sig.
 

Ilmater

Diamond Member
Jun 13, 2002
7,516
1
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Originally posted by: thorin
For the last time, AMD DOES base its PRs on P4s

Originally posted by: Ilmater
I've said it in forums before, and now an AMD marketing guy has confirmed it. Even though it seems that they base their comparisons on current P4 speeds, they still base their PRs on the same thing they did back when the first XPs came out. Read on:

The Inquirer article
Actually according the AMD page linked in the article it most definately IS based on P4 comparison. And I quote:

"...normalized to P4 3.06Ghz processor with......."

Also I'd like to know how PWC (in this document compared a P4 3.06 vs a 3000+ on Jan01, 2002 as seen on page 4, or at least why they've set the date to 2002 for their tests).

this document @ AMD also shows that the PR rating is based on comparison vs P4(s).

Thorin
Once again, nowhere in those articles does it say that the PR system is BASED on the speed of a relative P4. On the contrary, the AMD they use for comparison already HAS a PR assigned to it. Those charts are simply to say, "Here's how our processor - which happens to be labeled the 3000+ - ranks compare to our biggest competitor." In every other industry I can think of with more than one product, they base model numbers (or rating numbers) on how a certain product performs relative to the other products in that company's lineup. Why is this so hard to believe?! However, that same company will put its products up against competing products from OTHER companies to show its relative place in the market. That's all AMD is doing.

For the record, I am NOT an AMD fanboy, though I do own AMD products. The last computer I owned was based on an Intel PII 450 and it ran fine even when I got rid of it last October. It STILL played the most recent games. I simply want to set the record straight.
 

dullard

Elite Member
May 21, 2001
26,056
4,708
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That simply wouldn't happen in reality. Remember, a PR rating is only a quantification of relative performance. Once that relationship is identified, it simply scales. Any marginal performance increase/decrease is covered in the standard deviation of error in their testing methodologies. AMD and PwC don't have unlimited resources to simply produce, test, market, and sell chips that perform marginally better; their PR is still limited by logical hardware progression and limitations (which is why we don't see .1 multipliers).

Ok suppose all the scores go up on averge by 10%. But the motherboard, memory, Operating system, CPU, and video card were changed. Then how does the PR rating change? Note: this is typical of what happens between different audits - so this time it is a realistic comparison.

 

Ilmater

Diamond Member
Jun 13, 2002
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Originally posted by: tart666
Originally posted by: Ilmater
[...] and now an AMD marketing guy has confirmed it.
Wow, this surely settles it. Now that the sleaziest person at AMD (clearly an independent figure) confirms it.
/end{sarcasm}
Heh. While you make a valid point (man I hate marketers), his point about what AMD bases their PRs on is backed up by data and an external audit by PWC.
 

Ilmater

Diamond Member
Jun 13, 2002
7,516
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Originally posted by: apoppin
It is AMD's reply and clearly marketing FUD!.

The PR rating IS (positively and absolutely) tied to the P-4 (period) :p

If you believe otherwise you are an AMD fanboy or naive. ;)
Again, I agree with you about marketers, but your statement is just conjecture. I have facts to back up my claim, where are yours?

And you claim that marketers spit out FUD?
 

paralazarguer

Banned
Jun 22, 2002
1,887
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I have facts to back up my claim, where are yours

NO YOU DON'T! You don't have any facts at all. You just keep jumping up and down and gesturing wildly at a document which doesn't mention the PR system at all...
You're also a person who's obviously incapable of understanding things like alterior motives and politics...
 

chizow

Diamond Member
Jun 26, 2001
9,537
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Originally posted by: dullard

Ok suppose all the scores go up on averge by 10%. But the motherboard, memory, Operating system, CPU, and video card were changed. Then how does the PR rating change? Note: this is typical of what happens between different audits - so this time it is a realistic comparison.

I think you're looking at it the wrong way. Once a PR relationship is quantified in mhz, it should simply scale regardless of what platform the tests are run. You have to simply isolate the external factors that would skew results, such as chipset/platform improvements. If you wanted to run a comparson between the 2 CPUs to make sure the PR rating held up based on the previously identified mhz increase required to justify the PR rating, you would need to run BOTH cpus on the same platform. What you are suggesting is like comparing benchmarks of a GF4 Ti4200 on a KT266 and old drivers to a GF4 Ti4600 on an nForce2 board 8 months later.

Chiz
 

LikeLinus

Lifer
Jul 25, 2001
11,518
670
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Originally posted by: chizow
Those are limitations of the laptop platform in general, taking into consideration the chipset, onboard gpu, available RAM format, power saving features, slower HDDs, etc. etc. A PR rating is nothing more than a quantification of performance relationships; the CPU will perform at a higher quantified value compared to another laptop. You might as well ask why a P4 2.4 desktop performs better than a P4 2.4 laptop.

Intel doesn't make this claim that 2.4 laptop will perform equal to a desktop. It's well known they dont.

Also I'm not sure how much of the "laptop's" limitations there are on a CPU intensive test that only test what a CPU Can do, not the components that surround it.

Also one other question. Exactly HOW are they testing the performance of the Barton compaired to the older Tbirds?? They are testing these newer chips with newer motherboards that could affect performance (as you suggest that a laptop's counterparts would do). Then how is it truly a fair comparison if they are testing newer technology on a new slocket motherboard that performs better? This would only be if the test were performed on the CPU only, which wouldnt be affected on the chipset and other things. See the catch 22 here? Cant have it both ways. Either the laptop counterparts are the same performance, or the parts around them are affect test. Then you have to look further into WHAT they are testing with and how this test was originally created.

I could really care less, I guess i'm just not gullible enough to fall for this whole "PR is real, no really, it's true". Nothing you can make me say to follow like a sheep to AMD. Anyone with half a brain can tell their PR was created to match themselves to the mhz number of Intel so they don't lose ground or sales to Intel because of the P4's ability to pump up to a higher mhz.

The funny thing is...AMD started this whole thing by releasing the Athlon 1GHZ 3 whole days before Intel and then coming out with commercials saying they had the "fastest" chip on the planet and they were the first to 1GHZ. So Intel changed their strategy and buried AMD mhz for mhz. Now AMD all the sudden started saying "oh mhz doesn't matter, only true performance does"

While it's true, They picked a fight they couldnt win (probably didnt expect to lose so fast) and got burned. They stuck their tail between their legs and started the PR system.

While i love AMD and i love all three chips i own by them...I'm not fooled by their intentions to make money and to make themselves look better to "Joe Public" who doesnt know jack about computers.

They can keep their PwC paper, I know what the truth is :)
 

dullard

Elite Member
May 21, 2001
26,056
4,708
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I think you're looking at it the wrong way. Once a PR relationship is quantified in mhz, it should simply scale regardless of what platform the tests are run. You have to simply isolate the external factors that would skew results, such as chipset/platform improvements. If you wanted to run a comparson between the 2 CPUs to make sure the PR rating held up based on the previously identified mhz increase required to justify the PR rating, you would need to run BOTH cpus on the same platform. What you are suggesting is like comparing benchmarks of a GF4 Ti4200 on a KT266 and old drivers to a GF4 Ti4600 on an nForce2 board 8 months later.

But that is exactly what AMD is doing!

Here are some important stats of the computer tested:
2600+ audit
Epox EP-8K3A+ motherboard
256 MB memory
GeForce 4 4600 Ti
Western Digital Caviar WD1200 hard drive
Win XP Pro

2800+ audit
ASUS A7N8X motherboard
256 MB memory
Radeon 9700 128M - Driver 6.13.10.6143
Western Digital Caviar WD1200 hard drive
Win XP Pro service pack 1

3000+ audit
ASUS A7N8X deluxe motherboard
512 MB memory
Radeon 9700 128M - Driver 6.13.10.6218
Western Digital Caviar WD1200 SE 8MB buffer hard drive
Win XP Pro service pack 1

The average score was 14.7% better comparing the 2800+ to the 2600+. The median score was 10.5% faster. But they changed motherboards to a NForce2 motherboard, updtated the operating system, and put in a better video card. Many games are video card dependant - so how can these scores be even compared? The 2800+ PR is 7.7% higher than the 2600+.

The average score was 10.7% better comparing the 3000+ to the 2800+. The median score was 7.8% faster. But they doubled the memory, used the fastest ATA hard drive available, and used faster video card drivers. I hope you understand what those 3 changes can do to the speed of the programs tested (especially the hard drive on the office benchmarks) - so how can these scores be even compared? The 3000+ PR is 7.1% higher than the 2800+.

How can they tell how much of the performance boost was due to video card/motherboard/memory/operating system/driver changes? They should use the same setup each time!
 

LikeLinus

Lifer
Jul 25, 2001
11,518
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Nevermind, dullard show answers to the questions i was asking.

AMD's PR is seriously flawed (if even real). Just as i suggested, they change the components around them. The test are not kept scientifically as close as possible to each other. It's a load of crap.
 

mee987

Senior member
Jan 23, 2002
773
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ill agree that the PR system is somehwat inaccurate, but i dont see why so many people here are so pissed at AMD. how many people here buy based purely on info given by the manufacturer? we all buy based on benchmarks from a 3rd party. a lot of the general public may buy based on AMD's PR rating, but i think its more than accurate enough for those shmucks.
 

paralazarguer

Banned
Jun 22, 2002
1,887
0
0
mee987, I don't think we're pissed at AMD. We're just pissed at AMD's attempt to snow us by saying that the PR system is based on something other than the P4. They take us for naive idiots.
 

Ilmater

Diamond Member
Jun 13, 2002
7,516
1
0
Originally posted by: paralazarguer
I have facts to back up my claim, where are yours

NO YOU DON'T! You don't have any facts at all. You just keep jumping up and down and gesturing wildly at a document which doesn't mention the PR system at all...
You're also a person who's obviously incapable of understanding things like alterior motives and politics...
I've made my claim as clearly as possible, but some refuse to believe it.

A) Nobody argues that, at first, the PR numbers were based on performance relative to a T-Bird core.
B) An article on The Inquirer questioned whether or not this was still the case.
C) Richard Baker of AMD's North European Marketing Division, in response to that article, states that, "The basis on which [PR numbers] are calculated is the same as it has always been, neither the applications nor their relative weightings have been changed since the original 1.4 Ghz Athlon."
D) He then gives a link to an article that outlines the exact benchmarks used to determine the rating system.
E) As their method for testing between now and then has not changed, clearly they are still basing their model numbers on an Athlon 1.4.

If you would like more proof, I took the liberty of poking around AMD's site, and found this white paper on "AMD Athlon? XP Processor Benchmarking and Model Numbering Methodology." The document states:
Approximately three percentage points on this normalized overall desktop performance scale represent the typical performance difference that exists between different system price bands in the market today.
Later, they normalize the results of the benchmarks of different processors to the performance of a 1.4GHz T-Bird. As you can see, the models that are roughly 3% faster than their predecessors are also 100 points above them. As you can also see, this set of benchmarking programs was updated for the 2200+, which is why the comparison isn't using outdated benchmarks.

If the claims were true that they were using the P4 as their basis for the model numbers, based on the numbers in the normalized chart, AMDs model numbers would be higher than they are. However, I will say that it's interesting that the 2100+ is only 2.5 percentage points above the 2000+, and the 2200+ is only 1.9 percentage points above that. Regardless, this should be sufficient enough to disprove the notion that PR numbers are based on equivalent P4s.
 

mee987

Senior member
Jan 23, 2002
773
0
0
i think they know that we (tech competent people) know that its based on the p4, but they want to "officially" say its based on the tbird.
 

chizow

Diamond Member
Jun 26, 2001
9,537
2
0
Originally posted by: dullard
I think you're looking at it the wrong way. Once a PR relationship is quantified in mhz, it should simply scale regardless of what platform the tests are run. You have to simply isolate the external factors that would skew results, such as chipset/platform improvements. If you wanted to run a comparson between the 2 CPUs to make sure the PR rating held up based on the previously identified mhz increase required to justify the PR rating, you would need to run BOTH cpus on the same platform. What you are suggesting is like comparing benchmarks of a GF4 Ti4200 on a KT266 and old drivers to a GF4 Ti4600 on an nForce2 board 8 months later.

But that is exactly what AMD is doing!

Here are some important stats of the computer tested:
2600+ audit
Epox EP-8K3A+ motherboard
256 MB memory
GeForce 4 4600 Ti
Western Digital Caviar WD1200 hard drive
Win XP Pro

2800+ audit
ASUS A7N8X motherboard
256 MB memory
Radeon 9700 128M - Driver 6.13.10.6143
Western Digital Caviar WD1200 hard drive
Win XP Pro service pack 1

3000+ audit
ASUS A7N8X delux motherboard
512 MB memory
Radeon 9700 128M - Driver 6.13.10.6218
Western Digital Caviar WD1200 SE 8MB buffer hard drive
Win XP Pro service pack 1

The average score was 14.7% better comparing the 2800+ to the 2600+. But they changed motherboards to a NForce2 motherboard, updtated the operating system, and put in a better video card. Many games are video card dependant - so how can these scores be even compared? The 2800+ PR is 7.7% higher than the 2600+.

The average score was 10.7% better comparing the 3000+ to the 2800+. But they doubled the memory, used the fastest ATA hard drive available, and used faster video card drivers. I hope you understand what those 3 changes can do to the speed of the programs tested (especially the hard drive on the office benchmarks) - so how can these scores be even compared? The 3000+ PR is 7.1% higher than the 2800+.

How can they tell how much of the performance boost was due to video card/motherboard/memory/operating system/driver changes? They should use the same setup each time!

You're still looking at it the wrong way. You're comparing apples to oranges and dogs to cats. The numbers in the examples are enough for me to illustrate this point. You are calculating the performance differences taking the upgraded components into consideration, not AMD. I don't have their workpapers in front of me, but I'm willing to bet they tested a 2800+ and a few other cpus on the same testbed to ensure their mhz to PR relationship held true. Any competent benchmark would. You could probably do the calculations yourself by looking at the Barton review and calculating the differences in scaling between each CPU. Once you've done that, compare the overrall % differential to the PR differential and I think you'll find the relationship holds true.

You can tell how much of a performance boost is attained simply by testing the two processors on the EXACT same platform at any given point in time, not by comparing test results from the previous generation. Unfortunately, you can only test with the tools at hand, but by the same token, you're going to test new components on the best available platforms to maximize overall current performance. This is done in every single benchmark you see done today.