Athlon XP

LAST ATHLON XP PRICE CUT: October 27, 2003
And there won't be any more, because it's dead.


What's an Athlon XP?
Ever used a Thunderbird, AKA pretty much any Athlon from 900MHz to 1.4GHz? The Athlon XP is a revised version of the old Athlon Thunderbird designed for more scalability and better performance (see the next paragraph for more). If you've ever heard of the Athlon 4, this is it. (I guess they decided "Athlon 4" would be a little too copycattish, especially considering there wasn't an Athlon 2 or 3.)

Palomino cores are very much an improvement over their Thunderbird counterparts. First of all, they use less power and thus run cooler. Thankfully, at that; it's about time to start looking at ways to make the chip run cooler when people start talking enthusiatically about cooling methods that make absolute zero look like an oven. Additionally, the chip has much-improved (well, existent) hardware pre-fetch; hardware pre-fetch logic basically tries to anticipate what data will be needed from the computer's main memory next and preemptively loads this data into the processor's L1 cache. This alone has proven incredibly useful, as the Pentium III Tualatin has demonstrated. Various other features have been incorporated, but I suppose they're for a node on the Palomino core, should one be created. The end result of these? Overall, an Athlon XP 1800+ running at 1.533GHz wins about seventy percent of the time to the 2GHz Pentium 4 in benchmarks-- assuming the P4 uses the older-model core, the Willamette. (I'll explain this bit in a more detail later on.) If it faces a 1.8GHz P4 Northwood (the newer model), it's more or less tied.


Quanti-what? And what's this "XXXX+" stuff?
The Athlon XP uses what AMD like to call "QuantiSpeed Architecture"; this is a fancy term for "a new core". Part of the model naming scheme for this thing involves running at a lower clock speed than one would suspect from the name.

The main problem the past chips have encountered is this: Athlon 1.2GHz processors can easily outperform Pentium 4 1.5 Willamettes, but the trouble is, your average person sees nothing in a CPU's speed but raw clock speed. The XP takes a crack at marketing with its name; 1800+ implies that it does indeed run at 1.8GHz (and the + implies faster). They only have to state the real speed below a paragraph of redundant sentences that all boil down to "BETTER THAN 1.8", and so on. Even the BIOS hides the clock speed; in fact, overclockers have noted with amusement that the BIOS on some motherboards displays "Athlon XP 1900+" when overclocked to about 1.6GHz. (And by the way, yes, this scales alllll the way up to 2800+; I've tried it out with my rather willing 1700+). They seem afraid to mention it to the public; you know, the people that bought Pentium IIIs when the Athlon had already gone past 1GHz?

Athlon XP 1500s run at 1.333GHz, 1800s at 1.533GHz. AMD like to put this in certain magazine ads in not-so-fine print; something along the lines of "Processor does not run at 1.8GHz, but does outperform Intel processors at that speed". This means that a 1600 runs on boards that can't go any faster than 1.4GHz. Combined with that AMD seem to be sticking to Socket A (as stated earlier), most users are able to plug in an XP in the place of an old Athlon or even an old Duron, the idea of course not remotely related to selling more processors.

But it's not so simple. Thanks to the Bartons and improper scalings, the Athlon XP 2500+ (Barton core) actually runs at 1.833GHz, and the Athlon XP 2400+ (Thoroughbred-B core) runs at 2GHz default. Confused yet? So's everyone else. Then again, you could argue that Intel's the one to be blamed in the first place, with their early MHz == Speed campaigns. Your choice. At any rate, the numbers actually scale OK (2400+ is worse than 2500+ is worse than 2600+), which is much less confusing for Joe User than the A/B/C Pentium 4s. The end of this writeup has a list of all the XPs in existence, the possible core types, notes, and the steppings for them; if you have the CPU in hand and can see the little code thing, well, this is your chance.


Duron XPs?
The Duron offspring of the Palomino is the Morgan. It topped out at 1.3GHz, and industry analysts figured there was no sense in continuing with the Duron line anyway, since regular low-end Athlon XPs were so cheap.*** Then, in a move that surprised everyone, AMD announced late in August of 2003 that they would be reviving the Duron, with the new Duron "Applebred" cores being based on the Barton core but with 64KB of L2 cache instead of 512KB. (Actually, they're really more similar to the Thoroughbred-B, since the Barton is just a Thoroughbred-B with more cache; my best guess as to why they said it was based on the Barton core is to avoid confusion with the Thoroughbred-A Morgans and new Thoroughbred-B Applebred cores. Or maybe it's marketing.) The new Durons will have a 266MHz (dual 133MHz) frontside bus instead of the 200MHz frontside bus of the old ones, which should help performance some. The new ones are debuting at 1.4GHz, 1.6GHz, and 1.8GHz.

So why do these chips exist when the low-end Athlon XPs are so cheap? If you're asking this question, you probably live somewhere like the U.S. or the U.K. or Australia or wherever and don't quite get what market AMD is targeting. The Duron has an excellent reputation in places like Russia and Mexico, where the developing economy means that a low price is valued above all else. There is still quite a market for the Duron in places like these, since the Duron is the cheapest processor still in production. Whether or not the Duron will be exposed to the fully developed markets in countries such as the United Kingdom is a question that will only be answered by time; AMD have said that if there is enough demand in these countries, they will do so. (I finally buckled and made a Duron writeup, so there's more information about this stuff there if you're interested.)


Why aren't they ceramic now?
The chip is made out of an organic compound somewhat like the stuff that brown motherboards are made out of-- and, completely out of coincidence, the stuff Pentium 4's are made of. AMD claims this is more durable than the old ceramic model; most speculated that they picked it because 1. people were complaining about chips being so fragile that they spontaneously combusted in a user's hands and because 2. the Pentium 4s use it.

However, in reality, AMD did this for a much crueler reason. The new stuff has much lower electrical resistance than the old ceramic, meaning that the much-loved pencil trick is now a no-go. On the old ceramic stuff, resistance approached infinity-- the stuff was literally made out of insulator. On the new stuff, it's only around 1k ohm. What does this mean? Well, the resistance of a graphite bridge is about 1.6k ohm. That means that the new stuff is in fact less resistant than graphite, and that the pencil trick is impossible. The only way to unlock the processor without destroying it involves a multimeter, a scalpel, Krazy Glue, silver lacquer or molten copper, and a roll of tape. (You think I'm joking, but I'm not.)

But rejoice! The Palomino and Thoroughbred-A CPUs are shipping locked (with the bridges cut), but the Thoroughbred-B CPUs and Bartons are UNLOCKED. Unfortunately, anything with a default multiplier of 12.5 or below will only get to pick from multipliers between 5 and 12.5, and anything with a default multiplier of 13 or above can only select from multipliers above or equal to 13.

Okay, wait, stop rejoicing. AMD locked them again, because resellers were marking low-end XPs as higher-clocked chips. (Yeah, truly genius. They can stop people from marking 2500+es as 3200+es now! Oh, wait, the two have the SAME MULTIPLIER, don't they.) Week 39 (date code 0339, the date code is right to the left of the stepping) and newer Thoroughbred-Bs and Bartons are almost always locked.


Up against...
As of the third quarter of 2003, the Athlon XP's main opposition is the Pentium 4 Northwood. The newer-model Northwood processor runs cooler and more efficiently, to put it simply, and the Athlon XP has trouble beating it. While the Athlon XP has a higher IPC count (that is, it does more at the same clock speed), the Northwood's clock speed scales a hell of a lot higher. The Northwood goes all the way up to 3.2GHz, and the Athlon XP to 2.2GHz (3200+). The Athlon XP 3200+'s PR number is sort of misleading, as it is slower than the Pentium 4 3.2C.


Palomino, Thoroughbred ("B"), Barton? What?
Newer Athlon XPs run on the Thoroughbred core, which is for all intents and purposes identical to the older one but a little colder or hotter running. "Colder or hotter?" you say? Well, it's like this. The Athlon XP doesn't have so much headroom. When they make newer and faster processors on the same core, they adjust the stepping, which is basically fine-tuning the core so that it runs cooler at the same voltage.* The problem is that this didn't go so well for AMD-- the 1700+ and 1800+ have no problems running at 1.5 volts, compared to the 1.75 of a Palomino, but the 2200+ requires a whopping 1.65v. That wouldn't be so bad, except since it's made on a smaller process and thus has a smaller core, the 2200+ is a real scorcher. Not enough room to have the heat absorbed from.

A newer Thoroughbred emerged, in the forms of the Athlon XPs 2400+ and 2600+. It's called the "Thoroughbred Revision B," and it's supposed to be able to scale a lot better than the old Thoroughbreds. What's more, it runs cooler, which means overclocking is once again a reality instead of a distant memory as it was with the old T-breds. And by the way, T-bred is not to be confused with T-bird. T-bred is Athlon XP Thoroughbred, T-bird is Athlon Thunderbird.

The 2600+ murders the Pentium 4 2.53GHz in regular old head-on CPU tests. But when EVERYTHING is plugged in-- you know, like in a real computer?-- they're more and less neck-and-neck. The Pentium 4 has a nice fat 533MHz frontside bus, while the 2600+ is stuck at 266MHz DDR, meaning it's got less memory bandwidth. So maybe a higher FSB would counter that, eh? Well, read on.

AMD, responding to popular demand, countered with the 2700+ and 2800+, which had frontside bus speeds of 333MHz. This was an improvement, but the Pentium 4 still leads in terms of performance, even if it's more or less out of headroom too. The 2700+ and up are also pricey pieces of hardware; the main advantage of Athlons over Pentiums is that Athlons are a hell of a lot cheaper, and the high-end models aren't exactly cost-effective.

Then the Athlon XP "Bartons" came out. They offered a 512KB L2 cache, at the price of an increased core size, which makes for-- anyone?-- less chips per wafer, which in turn makes for higher prices. The Athlon XP 3000+ (a Barton) was aptly named, as it wasn't QUITE as good as the P4 3.06GHz, but comes so damned close that the comparison is mostly irrelevant. After all, the 3.06GHz is 3066MHz. Then the C-series Pentium 4s came out, with their 800MHz FSBs, and mopped the floor with the Bartons. The Athlon XP 3200+ brought the Athlon line up to a 400MHz frontside bus, but this wasn't nearly enough to put it at the level of the Pentium 4 3.2C's performance. Then AMD released the Athlon 64s, which beat the P4 3.2s bloody.


So, are there laptops with these?
Yes. You might think an Athlon would be badly suited to mobile work, but Athlon XPs actually put out less heat than Pentium 4s. The heat thing mostly dates back from the Pentium III era, when Athlons put out seventy watts of heat and above and the Pentium IIIs only put out thirty-something. The "low voltage" XPs (1400+ through 1800+) put out a maxmimum of 25 watts of heat. The standard mobiles put out a maximum of 35 (for processors such as the Barton 2200+) or 45 (Barton 2400+, 2500+) watts. There are also the desktop replacement chips with massive 75W maximum heat output ratings. (In case you haven't noticed, the numbering scheme for notebooks is completely different than it is for desktops.)


Is it dead?
Unfortunately for me, no. AMD plan to keep Socket 462/A for a while longer, and they're also migrating the Thoroughbred-B core to Socket 754 ("Paris" core, which is a strange mix of K7 and K8 by the looks of things) to create a new bargain line. They say that there will even be Thoroughbred-B 3200+es, which means the Athlon XP might be clocked as high as 2.5GHz. And that means I get to update this node again. Thrilling.


How do I pronounce "AQXDA"?
"Ah-quacks-dah."



INDIVIDUAL PROCESSORS LIST
If you're reading this list you probably know a little about the CPU in your system already. A few general notes on the list first..

• The steppings provided are basically the best at overclocking. If you don't feel like overclocking this old processor, the attributes that make a processor a good overclocker also make it a good underclocker/undervolter (meaning you can reduce the voltage and speed to make it run nice and cool). And remember, stepping is not the only factor in an overclock by far; overclockability can vary with date of production and revision of stepping, your system might not be able to overclock as well as the processor, and you might just get unlucky.


• Remember that the voltage of Thoroughbred CPUs may be lower, but they have less area to have their heat output absorbed from (Palominos are 129mm², Thoroughbred-A and -B are 80mm² and 84mm² respectively, Bartons are 111mm²). Also, Thoroughbred-Bs are better about heat output than the raw core size would suggest.


• You may have a processor with steppings not listed; I've only listed the known BEST steppings for the processor, and the runners-up, so you can safely assume you got a not-so-great one. If you have a stepping that's not listed under the CPU you have but IS listed under faster XPs, that means you got a CPU that was part of a batch that was originally going to be sold as faster CPUs but wasn't for whatever reason. This means you are a lucky duck.


• If your 2000+/2100+/2200+/2400+ thinks it's a Barton, you probably have a Thorton. Thortons are Bartons with half of the L2 cache disabled. In other words, they're Thoroughbred-Bs with larger-than-usual cores and a habit of confusing their users.


• No, I didn't list the goddamned mobile chips. They're confusing. With mobiles, the 2200+ and 2400+ are Bartons, the 1400+ exists, there are several different versions of the same core (yes, that's more than is normal)... trust me, it's more trouble than it's worth. And besides, they're not "Athlon XP" processors, they're "Athlon XP-M" processors. So there.

= Model Name =
Brief description/history of model.
Possible Core: Ordering Part Number (OPN). Clock speed (FSBxMultiplier). Voltage. Best steppings.
(Repeat for as many cores that exist for this model)


= Athlon XP 1500+ =
The Athlon XP 1500+ is the lowest-end Athlon XP in existence. It enjoyed brief popularity as the series' debut (the slowest CPU in a series usually does), but AMD didn't make it for long, and it never was terribly popular.
Palomino: AX1500DMT3C. 1333MHz (133x10.0). 1.75v. AGKGA and AGOGA are best.

= Athlon XP 1600+ =
The Athlon XP 1600+ is no longer in production by AMD. A Palomino, the 1600+ was more popular than its core and speed would suggest, though most of their popularity had subsided by around March 2003. Why? Well, there were plenty of 1600+ CPUs on the market, but AMD was no longer making them. So retailers wanted them out, lowering the prices to below $50 US (including shipping). This in itself would be incentive enough for plenty of people to buy them (and let's not forget a lot of older motherboards only fully support processors up to 1.4GHz), but it just happens that AMD had made a lot of higher-stepping 1600+ processors; I'm not sure why, but my best guess is that they had a lot of cores with steppings cleared for 2000+/2100+ CPUs that they knew wouldn't sell (remember, people buying at the high end want the newest stuff), so they just called them 1600+es and were done with it. This resulted in a lot of AGOGA and above 1600+es floating around, and it didn't take long for a couple people to post to various message boards that hey look, they got an AGOIA from this site and it overclocks really well. Most people are aiming for the 1700+ Thoroughbred-B CPUs now, though, and there aren't too many 1600+es left anyway. There are actually a few Thoroughbred-B (but not Thoroughbred-A!) 1600+es too, but the Palominos are awfully common, and I wouldn't count on getting a Thoroughbred.
Palomino: AX1600DMT3C. 1400MHz (133x10.5). 1.75v. AGOIA and AROIA are best, followed by AGKGA and AGOGA.
Thoroughbred-B: AXDA1600DUT3C, occasionally AXDA1600DLT3C. 1400MHz (133x10.5). 1.6v and 1.5v. JIUHB is best, JIUGB a distant second.

= Athlon XP 1700+ =
The Athlon XP 1700+ just won't go away and die like a good processor. There are Palomino, Thoroughbred-A, and Thoroughbred-B Athlon XP 1700+ CPUs. The Thoroughbred-B 1700+es are very very popular, because they have something of a reputation as excellent overclockers. They can easily go to 150% of stock speed (2.2GHz) with unremarkable cooling and sane voltage levels. Not bad for a CPU that sells for around $50, right? Except since there are so many flavors of 1700+, it's sort of hard to know what you're getting. Will you be blessed with a +4 DLT3C JIXIB of Goodness, or cursed with a -2 DUT3C RIUGA of Suckdom? The 1700+ Palomino and Thoroughbred-A are unremarkable, but ridiculously cheap. One last thing: the best date code for JIUHB 1700+ CPUs is supposedly 307 or 309, with anything below 307 considerably worse and Really High ones pretty good too. If you're actually examining the date code on your processor, well, you need a hobby. Maybe you could write about processors.
Palomino: AX1700DMT3C. 1466MHz (133x11.0). 1.75v. Steppings are the same as 1600+.
Thoroughbred-A: AXDA1700DLT3C. 1466MHz (133x11.0). 1.5v. AIUGA is the best you're likely to get; RIUGA is all right.
Thoroughbred-B: AXDA1700DUT3C, occasionally AXDA1700DLT3C. 1466MHz (133x11.0). 1.6v and 1.5v. JIXIB and NIUHB are best, JIUHB is still excellent..

= Athlon XP 1800+ =
The Athlon XP 1800+ was the fastest CPU when the Athlon XP was announced, a position soon taken over by the Athlon XP 1900+. It is mostly unremarkable now, and both Thoroughbred versions are pretty much identical to the 1700+. Like the 1700+, it is very cheap and easy to locate due to high yield and high demand.
Palomino: AX1800DMT3C. 1533MHz (133x11.5). 1.75v. Steppings are the same as 1600+.
Thoroughbred-A: AXDA1700DLT3C. 1533MHz (133x11.5). 1.5v. Steppings are the same as 1700+.
Thoroughbred-B: AXDA1700DUT3C, occasionally AXDA1700DLT3C. 1533MHz (133x11.5). 1.6v and 1.5v. Steppings are the same as 1700+.

= Athlon XP 1900+ =
The Athlon XP 1900+ is the sad, neglected older brother of the 1800+. It's not a terribly interesting processor, but it's worth noting that there aren't any Tbred-B 1900+es. I'm not sure why. It's pretty damned hard to locate a Tbred-A 1900+, too, but they definitely exist.
Palomino: AX1900DMT3C. 1600MHz (133x12.0). 1.75v. Steppings are the same as 1600+.
Thoroughbred-A: AXDA1900DLT3C. 1600MHz (133x12.0). 1.5v. Steppings are the same as 1700+.

= Athlon XP 2000+ =
The Athlon XP 2000+ is notable for.. uhh.. its big happy round number. These are pretty common, since 2000+ chips got cheap faster than 2100+ chips. There's not too much special about these, really.
Palomino: AX2000DMT3C. 1667MHz (133x12.5). 1.75v. Same as 1600+, except I've never seen anything worse than AGOGA.
Thoroughbred-A: AXDA2000DUT3C. 1667MHz (133x12.5). 1.6v. AJUGA is best, followed by AIUGA.
Thoroughbred-B: AXDA2000DUT3C. 1667MHz (133x12.5). 1.6v. Steppings are the same as 1700+.

= Athlon XP 2100+ =
Now it starts to get interesting again. AMD decided to switch to .13-micron (130-nanometer) process after the 2100+, so the 2100+ was the last Palomino. Deciding to not scale the Palomino any higher was an excellent idea; I was seeing some fire extinguisher case mods at this point. The 2100+ comes in all three "normal" (256KB L2 cache) flavors. The 2100+ dropped in price fairly soon after the 2000+, so you see quite a few of them.
Palomino: AX2100DMT3C. 1733MHz (133x13.0). 1.75v. Steppings are the same as 2000+.
Thoroughbred-A: AXDA2100DUT3C. 1733MHz (133x13.0). 1.6v. AJUGA is best, followed by AIUGA.
Thoroughbred-B: AXDA2100DUT3C. 1733MHz (133x13.0). 1.6v. AIXIB is best, AIUHB is still good.

= Athlon XP 2200+ =
Is it hot in here, or is it the Thoroughbred-A 2200+? The 2200+ outputs up to 68 watts of heat over just eighty square millimeters of space. That's right, .85 watts per square millimeter. This had to do with that AMD was clearly facing a brick wall for the Thoroughbred-A core, here; the 1900+ ran at one and a half volts, and the 2200+ was up there at 1.65v. Yeah, sure, that's a tenth of a volt less than the Palomino, but it's also got smaller transistors that should be able to work with less voltage. Amazingly, some people managed to overclock this reactor of a CPU with air cooling. Imagine that: if 1.65v is enough to make J. Random Heatsink cry with the Tbred-A, just think of the temperatures at 1.85v. Needless to say, these people mostly used fans that scared animals to do this. The Thoroughbred-B 2200+ is significantly cooler, naturally; it outputs about five less watts on average, has a little more area to spread it over, and has a redesigned core that aids with heat dispersion.
Thoroughbred-A: AXDA2200DKV3C. 1800MHz (133x13.5). 1.65v. AJUGA is best, followed by AIUGA.
Thoroughbred-B: AXDA2200DUV3C. 1800MHz (133x13.5). 1.6v. Steppings are the same as 2000+.

= Athlon XP 2400+ =
No, that's not a mistake. There's no Athlon XP 2300+ (although you see them in eMachines and whatnot sometimes; another pointless OEM-specific model, I guess). You see, a few days before Intel launched the Pentium 4 2.8GHz, AMD decided to one-up their existing 2.53GHz CPU (for the first time in a while, and the last time until the A64) and paper launch the Thoroughbred-B 2400+ and 2600+. (No 2500+, though one exists now.) They raised the clock to 2GHz for the 2400+, which deviated from their usual 66MHz per 100 points of PR rating, but it was probably a good idea, as the 2400+ is pretty evenly matched with the Pentium 4 2.4B. The 2400+ is a great processor for the money; at just over seventy bucks you get a fast CPU that doesn't run too hot and can overclock a couple hundred MHz. And let's not forget that there's only one kind of 2400+ out there, so you really know what you're getting. Imagine what it would be like if it were Thoroughbred-A, though.
Thoroughbred-B: AXDA2400DKV3C. 2000MHz (133x15.0). 1.6v. Steppings are the same as 2100+.

= Athlon XP 2500+ =
Released after the 2600+, the 2500+ is the slowest Barton core Athlon XP in existence. Its clock speed is just a few MHz above that of the Athlon XP 2200+, but its larger L2 cache gives it a decent performance bonus. It was never very expensive, and was fairly popular for people that want to try out the Barton without emptying their wallet. Nearly all 2500+es are capable of running at 200x11, the speed of a 3200+, without ANY voltage change whatsoever. I guess AMD didn't get enough duds to do anything more than bin according to demand.
Barton: AXDA2500DKV4D. 1833MHz (166x11.0). 1.65v. AQZFA is best, anything "up" from AQUCA letterwise will hit 200x11 without trouble or voltage adjustments.

= Athlon XP 2600+ =
The highest-end Thoroughbred-B at the core's initial release, and a marker of the last time AMD got to be at the top until the Athlon 64, the XP 2600+ enjoyed sales that would be expected of a top-dog CPU (if only for a few days, since the P4/2800 came out shortly after). AMD also made a version with a 166MHz FSB (333MHz effective), which had a slightly lower clock speed to adjust for the higher-clocked frontside bus speed. The Thoroughbred 2600+es are pretty pointless, but it's worth noting that the FSB266 models (the earliest ones, and the rarest ones) are the fastest CPUs supported by boards with a maximum FSB of 133MHz. (Then again, the 2400+ is only slightly slower, and a much safer bet, as there were only ever FSB266 versions of the 2400+.) The Barton 2600+ is interesting, as it was released later than the original 2600+, and even later than the original set of Bartons (2500+, 2800, 3000+), with no fanfare whatsoever. The reason for its existence remains a mystery.
Thoroughbred-B 133MHz FSB: AXDA2600DKV3C. 2133MHz (133x16.0). 1.65v. Steppings are the same as 2100+.
Thoroughbred-B 166MHz FSB: AXDA2600DKV3D. 2083MHz (166x12.5). 1.65v. Steppings are the same as 2100+.
Barton: AXDA2600DKV4D. 1917MHz (166x11.5). 1.65v. Steppings are the same as 2500+.

= Athlon XP 2700+ =
Released along with the 2800+, the 2700+ is a thoroughly unexciting Thoroughbred-B. It would have claimed the title of "slowest 166MHz FSB Athlon XP" (which is not likely to make anyone shiver with excitement, really), but the 2600+ stole that title. You don't see too many of these, because frankly they're boring CPUs occupying a small niche that I'm not sure what to call.
Thoroughbred-B: AXDA2700DKV3D. 2167MHz (166x13.0). 1.65v. Steppings are the same as 2100+.

= Athlon XP 2800+ =
The 2800+ is interesting because it was the first Athlon XP available with a Thoroughbred-B core and a Barton core. If that's not interesting to you, you've obviously not passionate enough about CPUs. The two are about the same speed in everyday use, but the Barton version is clocked a few MHz lower. AMD received a lot of flak for the original Thoroughbred-B 2800+, as they paper launched it to try and steal Intel's thunder when Intel released the Pentium 4 2.8. It was a while before the 2800+ was actually available, and even for a paper launched chip the 2800+ took way too long to arrive.
Thoroughbred-B: AXDA2800DKV3D. 2250MHz (166x13.5). 1.65v. Steppings are the same as 2100+.
Barton: AXDA2800DKV4D. 2086MHz (166x12.5). 1.65v. Steppings are the same as 2500+.

= Athlon XP 3000+ =
Ah, the 3000+. Now THAT's a big number. The 3000+ wasn't quite as competitive with the Pentium 4 3.06GHz as it could have been, unfortunately, and shortly after its release the C-series Pentium 4s came out and beat the pins off of the entire Athlon XP line. Was always a stupid buy, but you're more likely to find one for cheap nowadays. Still, you can probably get a 2500+ or something for less, and if you want more power then you shouldn't bother with the Athlon XP. There's also an FSB400 (200MHz in reality) FSB Athlon XP 3000+. If you're using a board only capable of a 166MHz frontside bus speed and lower, make sure you're not getting the FSB400/200MHz model.
Barton 166MHz FSB: AXDA3000DKV4D. 2167MHz (166x13.0). 1.65v. Steppings are the same as 2500+.
Barton 200MHz FSB: AXDA3000DKV4E. 2100MHz (200x10.5). 1.65v. Steppings are the same as 2500+.

= Athlon XP 3200+ =
The 3200+ was the end of the line for the Athlon XP, a suitably overpriced (at the time; value quickly became closer to what this thing was actually worth, of course) and alarmingly underpowered high-end part. It was and will likely always be a waste of money, as Athlon XP 2500+es are simply 3200+es with different stickers on them. The Athlon XP 3200+ is/was slower than the (contemporary) Pentium 4-C line in, uh, just about everything, though it does have a shiny 400MHz FSB. You can tell why people were losing faith in AMD at this point. Not to be confused with the Athlon 64 3200+, released on September 23rd, which clobbered the Pentium 4 3.2C.
Barton: AXDA3200DKV4E. 2200MHz (200x11.0). 1.65v. Steppings are the same as 2500+.





* If you're wondering why they don't just manufacture ALL of their processors on the new process or just do their research beforehand, there are in fact reasons. They don't do the stepping and such beforehand because it takes quite a bit of time. And as for making them all on the new process, do you think they want users to ignore the high-end processors and just take their low-ends, because they're really the same? There's a disaster for you. Still, every generation has its gem. For example, a lot of 1.0GHz Athlon Thunderbirds had the stepping of 1.4GHz ones (AXIA), and many Athlon XP 1600+'s right now actually have the stepping for 2100+'s. I won't even mention JIUHB. Pentium 4 Northwoods, 1.6A, 1.8A, 2.0A; these are all magic numbers, and I know the first two are guaranteed higher-end processors. This is a treat for everyone, because since the CPU is more efficient with its energy, you can run it at default speed and lower voltage (leading to a nice chilly CPU) or just get a free overclock out of them.

** Flames are welcome.

*** Zerotime says re Athlon XP: Even in the days of the Thunderbird-based ones it was worth shelling out an extra $20 or so and not getting the Duron. I remember buying my 1200c for AUD$140 (wholesale :) and the Duron 800 only being about $110 or something.