TBreds or Low Breds?

Introduction

We are just starting to see TBredBs showing up at rather low speeds.

Just last night, Newegg offered a TBred something (more on this below) at the 2100+ speed.

Newegg is out of them now, but as you’ll see, there’s a few reasons not to jump on the bandwagon immediately.

Many, many people have been waiting a long time to get a low-speed TBredB and get 2.3GHz performance from a CPU costing much less than $100.

However, to get one of these things, and not something else, you’re going to pay attention to a number of minor details, and so far, even people who are aware of such details are messing up as often as not.

This is unfortunately very confusing, with two or even three different types of processors being sold under the same speed, and in some cases, even order numbers won’t help you.

Secondly, there’s some early indications that at least some of the low Breds don’t perform at anticipated TBredB levels.

Ed Stroligo

Which Codes Mean What

To make this easy, what you need to know is listed by processor speed.

The OPN information is printed somewhere on every AMD CPU. For all Palominos, if you’re looking at one, the OPN is the first code printed on the core of the CPU located in the middle of the processor. For all Thoroughbreds, the OPN the first code printed on the black area on one edge of the CPU.

This information is based on current AMD datasheets. These are subject to change, but AMD usually doesn’t put new processors out before changing the datasheets.

For low-speed (i.e sub-2400+) Athlon XPs, there are two critical indicators in the OPN.

AX1700DMT3C: Voltage
AX1700DMT3C: Maximum temperature

The following codes mean the following:

Voltage

L: 1.50V
U: 1.60V
K: 1.65V
M: 1.75V

All Palominos have default voltage of 1.75V, so all Palominos have voltage code of “M.” TBredAs have a default range of 1.5-1.65V. TBredBs have a default range of 1.6V-1.65V.

Maximum Temperature

T: 90C
V: 85C

All AMD processors with a rating less than 2200+ have a maximum temperature of 90C, so they’re all “Ts.” Anything above that has a max temp of 85C, so they’re all “Vs.”

Here’s how these codes translate in real life with real chips:

1600+

Palominos: If the website you’re ordering from shows an order code of AX1600DMT3C, that’s a Palomino.

TBredB: If the website you’re ordering from shows an order code of AXDA1600DUT3C, that’s a Thoroughbred B.

1700+

Palominos: If the website you’re ordering from shows an order code of AX1700DMT3C, that’s a Palomino.

TBredA: If the website you’re ordering from shows an order code of AXDA1700DLT3C, that’s a Thoroughbred A. Update 3/28/03: It appears that from week 8 of 2003 and afterwards, there are 1.5V TBredBs with the same code.

All TBredAs have a stepping code which ends in “A,” like “AIUGA.” All TBredBs have a stepping code which ends in “B,” like “AIUGB.”

TBredB: If the website you’re ordering from shows an order code of AXDA1700DUT3C, that’s a Thoroughbred B.

If you see a code like “AIUHB” that begins with the letter “A” on the second line of the processor codes, that’s a high-end TBredB.

If you see a code like “JIUCB” that begins with the letter “J” on the second line of the processor codes, that’s a low-end TBredB.

As of now (1/15/03), all TBredBs sold at this speed are low-end “J” TBredBs.

1800+

Palominos: If the website you’re ordering from shows an order code of AX1800DMT3C, that’s a Palomino.

TBredA: If the website you’re ordering from shows an order code of AXDA1800DLT3C, that’s a Thoroughbred A. Update 3/28/03: It appears that from week 8 of 2003 and afterwards, there are 1.5V TBredBs with the same code.

All TBredAs have a stepping code which ends in “A,” like “AIUGA.” All TBredBs have a stepping code which ends in “B,” like “AIUGB.”

TBredB: If the website you’re ordering from shows an order code of AXDA1800DUT3C, that’s a Thoroughbred B.

If you see a code like “AIUHB” that begins with the letter “A” on the second line of the processor codes, that’s a high-end TBredB.

If you see a code like “JIUCB” that begins with the letter “J” on the second line of the processor codes, that’s a low-end TBredB.

As of now (1/15/03), all TBredBs sold at this speed are low-end “J” TBredBs.

1900+

Palominos: If the website you’re ordering from shows an order code of AX1900DMT3C, that’s a Palomino.

TBredA: If the website you’re ordering from shows an order code of AXDA1900DLT3C, that’s a Thoroughbred A.

TBredB: If the website you’re ordering from shows an order code of AXDA1900DUT3C, that would be a Thoroughbred B.

If you see a code like “AIUHB” that begins with the letter “A” on the second line of the processor codes, that’s a high-end TBredB.

If you see a code like “JIUCB” that begins with the letter “J” on the second line of the processor codes, that’s a low-end TBredB.

However, AMD’s datasheets do not currently show a 1900+ TBredB, and as of now (1/15/03), there have been no sightings of any. Since both the 1800+ and 2000+ TBredBs have a default voltage of 1.60V (“U”); it’s very safe to say any 1900+ TBredB will also.

2000+

Palominos: If the website you’re ordering from shows an order code of AX2000DMT3C, that’s a Palomino.

TBredA: If the website you’re ordering from shows an order code of AXDA2000DKT3C, that’s a Thoroughbred A.

TBredA/B: If the website you’re ordering from shows an order code of AXDA2000DUT3C, that could be either a Thoroughbred A or Thoroughbred B. The only way to distinguish between the two is by the stepping code.

All TBredAs have a stepping code which ends in “A,” like “AIUGA.” All TBredBs have a stepping code which ends in “B,” like “AIUGB.”

There’s two listed TBredA types in the AMD techdoc. One uses 1.6V, the other uses 1.65V. The TBredB is solely 1.6V.

If you’ve determined a CPU is a TBredB, if you see a code like “AIUHB” that begins with the letter “A” on the second line of the processor codes, that’s a high-end TBredB.

If you see a code like “JIUCB” that begins with the letter “J” on the second line of the processor codes, that’s a low-end TBredB.

As of now (1/15/03), there have no sighting of TBredBs, and only one sighting of a TBredA at this speed.

2100+

Palominos: If the website you’re ordering from shows an order code of AX2100DMT3C, that’s a Palomino.

TBredA/B: If the website you’re ordering from shows an order code of AXDA2000DUT3C, that could be either a Thoroughbred A or Thoroughbred B.

All TBredAs have a stepping code which ends in “A,” like “AIUGA.” All TBredBs have a stepping code which ends in “B,” like “AIUGB.”

If you see a code like “AIUHB” that begins with the letter “A” on the second line of the processor codes, that’s a high-end TBredB.

If you see a code like “JIUCB” that begins with the letter “J” on the second line of the processor codes, that’s a low-end TBredB.

As of now (3/28/03), the only sighting of 2100+ TBreds have been TBredsBs, and they have all been high-end TBredBs.

2200+

TBredA: If the website you’re ordering from shows an order code of AXDA2200DKV3C, that’s a Thoroughbred A.

TBredB: If the website you’re ordering from shows an order code of AXDA2200DUV3C, that’s a Thoroughbred B.

If you see a code like “AIUHB” that begins with the letter “A” on the second line of the processor codes, that’s a high-end TBredB.

If you see a code like “JIUCB” that begins with the letter “J” on the second line of the processor codes, that’s a low-end TBredB.

As of now (1/15/03), no TBredBs have been sighted at this speed.

2400+

Sorry, no exciting choices here (yet). They’re all TBredBs, and they’ll have an order code of AXDA2400DKV3C.

Yes, the DKV part is the same as for the 2200+. That’s because a TBredA runs at 1.65V (that’s what the “K” stands for) at 2200+. A TBredB runs at 1.6V (that’s what the “U” stands for) at 2200+ and 1.65V at 2400+ and above.

As of now (1/15/03), all sightings of the 2400+ and faster CPUs have been high-end TBredBs.

2600+

These are all TBredBs, too, but just in case “which one I am getting” is getting old, the 2600+ gives you a new, different challenge: What Speed Am I Getting? There will be two 2600+s, but they’ll run at different speeds. Since the 333MHz bus helps performance, AMD figured (correctly) that a CPU running at a slightly lower speed and higher bus was the same as a CPU running at a higher speed and a lower bus.

The 2600+, 266MHz version, will run at 2133MHz.

The 2600+, 333MHz version, will run at 2083MHz.

We’ll no doubt see more situations like this as the number of 333MHz processors expands.

The way you tell these apart by OPN is that the 266MHz processors will always have an OPN that ends in “C,” while the 333MHz processors will always have an OPN that ends in “D.”

How To Buy

There’s two ways to buy a CPU, either over a website, or in person.

Websites rarely list CPUs by stepping code. They will, however, sometimes list CPUs on their webpages and provide their OPNs. That’s the ordering number.

So long as we have all these different type processors around, you should NOT order from any place that doesn’t have the OPN listed along side the processor. If you do, you could well end up with a Palomino when you expected to get a TBred, or get a TBredA when you expected a TBredB. After all, the webpage said you were going to get an XP1800 or whatever, not that it was a Thoroughbred. If you want to send it back, expect to get hit with a restocking fee if the place has one.

On the other hand, if you order from a reseller that shows the OPN on the webpage (and save the webpage) and the OPN on the webpage indicates a Thoroughbred, if you get a Palomino, you’re protected. They didn’t send you what you ordered, and you have proof of it.

If you think I’m overly paranoid, well, I’ve been in this situation, and it works.

Never accept a salesman’s verbal word that you’ll get the “right” one. Most places have their goods in warehouses, often miles and miles away. The salesperson couldn’t find out even if he wanted to, and many salesmen will tell you anything to get the sale, then deny it later. Always get it in writing before you order, any reputable place will be happy to do that if it’s possible.

Website pages aren’t always accurate. If there is any contradiction in the description of the item (i.e., the product is called .13 micron or “latest technology,” but it has a Palomino OPN, either find another place, or email the reseller asking for written confirmation on just what it is they are selling.

What I’ve said works fine with OEM chips; retail boxes are another story, especially if you’re buying in person. I just looked at a TBredA box, and there is no obvious indicator what kind of processor comes in the box. (There is a sticker with a code like 19-103-352, but that doesn’t correspond to any codes we’re aware of yet).

Ed

Most AMD processors have codes that begin with the letter “A.” Not all.

Occasionally, there are those that don’t. They start with a different letter of the alphabet. For instance, there were AIRGAs and there were also RIRGAs.

Up to now, those AMD CPUs whose code starts with a letter other than “A” have not performed as well as those with otherwise the same code that do. So RIRGAs did worse than AIRGAs.

The first low-speed TBredBs have codes like JIUCB and JIUGB, and initial indications are they don’t do as well as the TBredBs whose code do begin with “A” (and not much better than late-model TBredAs).

Could it be that these are CPUs that couldn’t quite cut it at higher speeds? That’s very possible, especially considering AMD’s difficulties in getting them out to begin with.

It’s still very early, but those who want more than a little over 2GHz had better wait some more.

Update 1/11/03: (this material is also found in http://www.overclockers.com/tips00246)

A couple more 1700+ low Breds have been received and tested by folks out in Forumland, and they didn’t do too well, either.

However . . . .

We do have a report on a TBredB 2100+. It’s not a “J.” It’s an “A” chip, an AIUGB chip in fact, and this one did a whole lot better than the “J”s are doing, on par with the more expensive XPs.

This is not to say you’ll get 2.5GHz out of one, too, but these “A” 2100+s look to be true kin of the 2400s and better, while the “J” chips do not.

You’ve Got To Ask Yourself One Question: Do I Feel Lucky?

The CPU described above did not come from a particular retailer.

However, one place might be selling it. Newegg is now offering 2100+s that are TBreds (it’s the $97 and only the $97 item on that page).

And yes, unlike a day or so ago, you can actually order one from them.

On the one hand, Newegg calls it an “AXDA2100DLT3C” in one spot (which it can’t be, no 2100+ can have that designation) and “AXDA2100DUT3C” in the other (which is can be, but that could be a TBred A or B.

On the other hand, the picture of the product is definitely an “A” TBredB like the one described above.

If Newegg is shipping what’s in the picture, this is the TBredB you want, not a “J” chip.

On the other hand, it could be something else.

For those of you who have to be sure, we’ll know one way or the other towards the end of next week as early buyers report on what they get. It’s not like this is a one-time sale; we know they’re out there.

Or do you feel lucky?

Why Don’t You Buy One And Find Out For Us?

I just did. I felt lucky. :)

Ed

Voltage Mods

Over the past number of months, people have been coming up with ways to change the default voltage of Intel PIV chips without changing the processor, either by wrapping thin wires between certain pins on the processor, or more recently, using conductive ink to connect pinholes.

Recently, someone in our forum did the same wirewrap trick with TBreds, and since the relevant pins are adjacent to each other, there’s no reason to believe the conductive ink approach wouldn’t work, either.

This is especially appropriate for those with motherboards that allow only limited or no voltage adjustment on the motherboard. It doesn’t seem to get you more than 1.85V, though (that’s because XPs have a maximum voltage of 1.85V; getting more than that requires other modifications).

Temperatures

These things are getting pretty toasty even at 2GHz, and less than optimal cooling could prove a barrier even at those speeds. I read an account someplace of someone who couldn’t get past 2GHz with an air-cooled system, but could after he opened up the window and let some of that winter air in.

In any case, overclocking up to around 2.3 or better with even just a little extra voltage is going to mean wattage in the neighborhood of one watt per sq. millimeter. That may not be hot as hell, but it’s close, and demands high-quality air cooling at a minimum.

The Real Nightmare

As you saw on page two, telling TBredAs and TBredBs apart can be pretty rough. Up to now, though, we haven’t seen more than one particular type of TBred being sold in any speed class.

What we don’t know is how many TBredAs made for higher speeds and stockpiled while the Palominos were being flogged off are sitting around in AMD’s inventory waiting to be sold.

I think the Newegg 2100+s will be a leading indicator of that. Will they be TBredAs that have been gathering dust? Are they TBredBs?

The real nightmare will be if they’re both. There will be no way to tell besides visual inspection of OEM chips to tell (in the case of 2000+s and 2100+s) which is which

A Frustrating Trip

Loyal AMD fans have had a rough time of it. They’ve waited forever for cheap Tbreds, and now that they are starting to arrive, they’ll have a hard time finding the right one inbetween the Perpetual Palominos and TBredAs. A lot of people will not make the effort and pay for it with the wrong processor.

Even those who get through that may well find that what they have is indeed a little brother to the much more expensive TBredBs.

It’s hardly a grave injustice and AMD can hardly be denounced for ripping people off by selling them $60 processors capable of 1.9-2GHz.

But people are funny. They don’t buy a CPU; they make up a fantasy about it and buy that. If the fantasy doesn’t come true, no matter how unrealistic it was, it’s the company’s fault, and the reaction is often, “I’ll never buy for them again.”

For a lot of people, buying this kind of equipment is an emotional purchase, and they react emotionally when they don’t get what they want.

AMD is having enough problems as is. The idea behind an article like this is not only to keep you from personal disappointment, but also to keep AMD from suffering the consequences of that disappointment.

But you have to help yourself a little, too.

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