Why doesn't Athlon nnnn XP = nnnn MHz?

[ricercar]

When I returned to the x86 hardware scene this summer, it took me a while to learn that AMD's Athlon 1600 XP was not a 1600 MHz device but instead a 1400 MHz device.

WTF?

So when I read that the nForce2 boards support an Athlon 2800 XP, I realized I have no idea what the CPU clock speed is. (Sure I can look it up in a review, but my point is that I shouldn't have to!) Is there a conversion/proportion/ratio between the XP numeral and MHz, or is it all marketing whimsy?

[thcdru2k]

its compartive performance to a p4 of same clock speed. so athlon xp would be just as fast, or faster or slower in some cases to a p4 1.6ghz.

[ricercar]

So, my Athlon 1600 XP at 1402 MHz is the equivalent of a Pentium 4 at 1600 MHz. Hrmmmm. OK. The 2800 XP is therefore equivalent of a P4 at 2.8GHz. At least there's a method to the madness.

Thanks for the instant reply. I sometimes forget that I'm not the only person with insomnia. :eek:

[Kruno]

It's really called HYPE. :)

[Ryo-Ohki]

It's really meaning you don't have to push the MHz to have a better processor. A better-thought, or at least more optimized architecture, is all you need.

[ricercar]

The AMD "Hammer" CPU architecture is optimized to directly address main memory, bypassing the northbridge. While this appears to be good for the CPU, doesn't this screw graphics processors, causing an extra level of indirection between AGP and main memory?

Previously the northbridge was interposed between the AGP card and main memory. Won't the Hammer architecture cause an AGP GPU to negotiate with (1) a northbridge and then (2) the Hammer CPU before it can address main memory?

What am I missing? (I thought AMD and NVIDIA were friends.)

[StealthHawk]

the real question is how often does the graphics card access main memory, and should games ever be programmed so that it does? main memory is just so slow that i don't see why you would ever want to have to transfer data over it.

[ricercar]

I thought textures were stored in the main memory rather than video card memory. If this is valid, then as games grow more demanding, there will be more demands on main memory access.

[Kruno]

Might I add: DOOM 3 BABY!!!!!!!!
"...80Mb of textures..."

[SavagePaladin]

It could easily have a differently optimized AGP architecture, so I doubt its that big a deal.

[StealthHawk]

Originally posted by ricercar
I thought textures were stored in the main memory rather than video card memory. If this is valid, then as games grow more demanding, there will be more demands on main memory access.

no, that is what AGP texturing is all about. most games don't use AGP texturing though, because as i mentioned above, it's horrendously slow. just compare the memory bandwidth of a high end video card to the system memory bandwidth. ick.

[ReDeeMeR]

Yup, Go AMD! :D

[PoGGeh]

OK seems ya'll need a lesson.

The XP rating is NOT, I repeat NOT NOT NOT, to do with the Pentium 4. Thats right, NOT!!!

The XP rating is based on previous chips. Due to optimisations in the instruction sets the new Athlons run better than the old. So a 1400 new 'bird with SSE and such, runs as the same speed as an old one would IF it was 1600.

So they run the same, but the new cores can process stuff quicker. Hence 1400 = 1600XP

BTW if you werent listening. It has Absolutely NOTHING to do with the P4.

EDIT : Pah!! Geforce 2? Just sold that to buy my nice new 9700 :P

[StealthHawk]

Originally posted by PoGGeh
OK seems ya'll need a lesson.

The XP rating is NOT, I repeat NOT NOT NOT, to do with the Pentium 4. Thats right, NOT!!!

The XP rating is based on previous chips. Due to optimisations in the instruction sets the new Athlons run better than the old. So a 1400 new 'bird with SSE and such, runs as the same speed as an old one would IF it was 1600.

So they run the same, but the new cores can process stuff quicker. Hence 1400 = 1600XP

BTW if you werent listening. It has Absolutely NOTHING to do with the P4.

EDIT : Pah!! Geforce 2? Just sold that to buy my nice new 9700 :P
sure, that is what AMD tells us, and you swallowed it hook, line, and sinker. the fact is that AMD only implemented the system after the P4 starting hiking up clock speeds. the causality for AMDs move was clearly not performance over previous chips, but a public relations move to make their chips look more attractive compared to the "falsity" of the Pentium 4 performance.

as a side note, it is interesting then that with the Tbred performance ratings, there is more clockspeed backing them up. so Palomino PR ratings were higher than they should have been

[SavagePaladin]

Actually what he said was right. The reason for the new ratings was as they've said...the system needed a rework.

If you compared a tbird to a XP then, you probably would have agreed with them. The fact that a Palomino rating tended to perform better than higher p4 speed agrees.

I have no idea what they're basing the new ratings on. Can't honestly say I care anymore.

[Harnagel]

I would have to cast my vote with StealthHawk. It doesn't make any sense to rate your products according to past generations. Otherwise we would all be buying AthlonXP 20000s (which really run at 1800Mhz) because it's the equivelant of an 8086 running at 20000Mhz.

It does make sense to have a model rating system so that the uniformed public can compare price to performance ratio. That way if Joe Dirt Farmer walks into a store and sees an AthlonXP2000(running at 1667Mghz) and a Pentium4 2Ghz he will draw the conclusion that they are equivalent products. The rating system wasn't created for enthusiasts like us who benchmark systems or read reviews of the products we buy.

[Kruno]

Stealth and you make correct points. Anyway wasn't this discussed before and everyone is just repeating themselves?

Only cpu's I know that are over 1.5GHz are Athlon's and P4's, so it's nice to guess that AMD are competing with Intel. :)


Originally posted by PoGGeh
OK seems ya'll need a lesson.

The XP rating is NOT, I repeat NOT NOT NOT, to do with the Pentium 4. Thats right, NOT!!!

The XP rating is based on previous chips. Due to optimisations in the instruction sets the new Athlons run better than the old. So a 1400 new 'bird with SSE and such, runs as the same speed as an old one would IF it was 1600.

So they run the same, but the new cores can process stuff quicker. Hence 1400 = 1600XP

BTW if you werent listening. It has Absolutely NOTHING to do with the P4.

EDIT : Pah!! Geforce 2? Just sold that to buy my nice new 9700 :P

[StealthHawk]

Originally posted by K.I.L.E.R
Stealth and you make correct points. Anyway wasn't this discussed before and everyone is just repeating themselves?

Only cpu's I know that are over 1.5GHz are Athlon's and P4's, so it's nice to guess that AMD are competing with Intel. :)

yeah, i'm pretty sure it has. not so sure whether or not it happened after nV News was wiped out though, but then we all know that most people don't look at threads after the first page(sometimes not even that) before making a new thread of asking the same question.

but anyway, i'm sure that you've noticed that similar arguments keep recurring every few months, and we might as well reply to them early on before they turn into flame fests between some of the more outspoken members.

plus, i gotta keep the post count coming in case Corporal Dan ever comes out of retirement. that guy was crazy, averaging over 20+ posts a day.

[Ambian]

AMD put it well, in their own words, but I cannot find that exact url.

They made an analogy which looked somewhat like this:
Consider an AthalonXP processor as a 6 cylinder engine, and the competition as a 4 cylinder one. Although the 4 cylinder is capable of running equal or higher rpm, the 6 is able to put out much more power per cycle, and will blow the doors off the 4 cylinder.

[Dazz]

In fact the PR rating is going against the classic Athlon a Athlon XP 1600+ is the same speed as a Classsic Athlon (512k) or AMD Duron (64k) If it could run at 1600MHz. It just so happens the P4 (256K) runs slower then the P3 or Tbird (A step back eh!) so a Athlon XP 1600+ was as fast as a Pentium 4 1800MHz (256) however the Northwood Pentium 4 (512k) runs as fast as a Athlon so, so it was a Athlon XP 1600+ Vs Pentium 4 1.6A (512). Later on they decided to change that as people compaired them against the P4 anyway so now they modifiy it against the Pentium 4 starting with the Athlon XP 2400+ they had to town down the clock due to the Pentium 4's bus increase to 533MHz.

[SavagePaladin]

The 'classic' Athlon had half speed or lower cache, so I doubt that. Thunderbird is what you mean :p

[Ambian]

the classic athalon had only 256K L2
and if you tested two systems (duron and AXP) running the same multiplier and FSB settings (let's say 10.5x133, standard for a 1600+, but using an overclocked duron at 1400MHz) you would find that ANY processor-related benchmark will produce more points for the XP. NQA.

[SavagePaladin]

Originally posted by Ambian
the classic athalon had only 256K L2
and if you tested two systems (duron and AXP) running the same multiplier and FSB settings (let's say 10.5x133, standard for a 1600+, but using an overclocked duron at 1400MHz) you would find that ANY processor-related benchmark will produce more points for the XP. NQA.
my classic athlon has 512k half speed RAM. my athXP has 256k full speed, as did the thunderbird

[SocketAzzWipe]

Originally posted by K.I.L.E.R
It's really called HYPE. :)
Whatever...P4s have hype built into them ...empty mhz...a 1.8 gig XP can kick the snot out of your P4 @ 1.8...don't be talking about hype, fool! :mad:

[StealthHawk]

Originally posted by SavagePaladin
my classic athlon has 512k half speed RAM. my athXP has 256k full speed, as did the thunderbird

yes, the original Athlons had 512K cache, mostly running at half the clock speed. the later Athlons however dropped down to 1/3 the clock speed :(