AMD has recently revised its techdoc for Athlon XPs, and there's some interesting changes (look at page 23).

1) There is now a 1600+ TBredB included on the list. Up to now, all 1600+s have been Palominos.

In all likelihood, AMD introduced this to make OEMs have and/or clear out some marginal processors (you'll see why I call them "marginal" in a moment).

How to tell them apart?

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 AXDA1700DUT3C, that's a Thoroughbred B.

Are they out there? Not yet, but if you're interested, you might want to check those places that sell 1600+s but are temporarily out-of-stock. The new stock may be these chips.

2) There are now 1.5V TBredBs. Up to now, one way to tell a TBredA apart from a TBredB has been that only TBredAs had a default voltage of 1.5V. No more.

Both the 1700+ and 1800+ TBredBs are now coming in both 1.5V and 1.6V versions, so a TBredB can now have a code like AXDA1700DLT3C.

The 1600+ TBredB only comes in a 1.6V flavor, which makes you wonder if they aren't a bit on the dreggy side. I'm sure some will find out one way or the another once they show up.

How do you tell a TBredA AXDA1700DLT3C from a TBredB AXDA1700DLT3C?

The hard way is to look at the stepping code. A TBredA will have a stepping code that ends in "A," like AIUGA. A TBredB will have a stepping code that ends in "B," like JIUHB.

The easy way is simply to go to ExcaliberPC and order from them.

No, we didn't get paid to say that, we have no relationship of any sort with the company. It's just that they're the only reseller we're aware of that lists stepping and week codes on the website and guarantees that that is what you'll get. This makes life a lot easier for overclockers. We think companies that do nice things for us, we should patronize them. If other places start doing the same thing, we'll mention them, too.

Should you investigate the "easy way," you'll notice that the most recently produced processors have a price premium over earlier ones. There's a reason for that.

The latest "J" series processors from AMD seem to be doing a bit better, particularly the 1.5V version, as this forum thread documents. On the one hand, they're reaching higher speeds at lower voltages than earlier "J" series processors.

On the other hand, the price between these and 2100+s from Newegg is down to just $16, and a few people reported that these "J"s just don't show errors when Prime95 doesn't work right, they reboot.

So this isn't an OMG, but an improvement is an improvement.

Email Ed