I have a theory...

In the stepping codes of XP chips I am wondering if the following applies:

For the letter first after the production date, does a number further down the alphabet denote a higher-speed capable processor? i.e. do RPMWs do less well than VPMWs at the same voltage?

Just a thought - some good evidence wouldn't go amiss though

Here's what's up:

AIUHB 0248MPMW?

MPMW

- The first letter is inconclusive.

- All Athlon XP's have a P as their second letter.

- Those with lower third letters consistently do better than those with higher ones, this is considered to indicate wafer integrity.

- Every AMD ever ends in a W.

Best code seen beginning of August 2003 and earlier:

newegg 2000+ DUT3C AIXHB 03xx xPAW

L337 M33P said:

In the stepping codes of XP chips I am wondering if the following applies:

For the letter first after the production date, does a number further down the alphabet denote a higher-speed capable processor? i.e. do RPMWs do less well than VPMWs at the same voltage?

Just a thought - some good evidence wouldn't go amiss though

Click to expand...

looks like a poor theory to me.

just full of guestimation.

c627627 said:

- Those with lower third letters consistently do better than those with higher ones, this is considered to indicate wafer integrity.

Click to expand...

This is interesting. I'll have to check mine when I get home (I have it written down somewhere if I haven't lost it).

AMD won't say.

This is all speculation + it's an "all things being equal" thing.

That means everything else being the same, and if you had a choice, which you won't, if the third letter is closer to A than to Z, those CPUs have been known to overclock a little better, all other things being equal.

Ha-ha, before taking on the OC Detective this time I'm calling in the cavalry.

Gautam will post details, hopefully soon.

Lol - I dont have a closed mind to the speculation just would like some conclusive proof on the matter!

Yea, I was wondering that too. What exactly IS wafer integrity? Only started hearing about that lately.

Oops I seem to have bumped this thread - due to new CPU I needed an excuse

Originally posted by c627627
AMD won't say.

Click to expand...

They didn't say anything to me at all when I called a while back to ask them about tbred B's. In fact they told me that there was no way to visually tell an A from a B without some sort of software. They even denied the die area was larger on a B.
I don't think they're overanxious to give the OCing community any more info than they have to. Anything we can figure out by swapping our own info is apparently more than they'll ever be willing to say.

At least we can tell things from the different codes on the AMD chips, I am not sure that you can with Intel. Nobody ever talks about the steppings and things with Intel chips. Of course there aren't as many Intel overclockers as there are AMD.

yea AMD ROCKS

I'm not very much against OC Detective. Austin was where I first got this info from, btw. What first gave me a heads up about the third letter being significant were the GameVe DLT3C's. Unlike the ones from Excal and Svc, these were nothing spectacular at all. They did about as well, if not worse as a DUT3C, maxing out at 2.2-2.3 on air, 200mhz or more below the DLT3C's. The only thing that looked odd in their stepping codes were the third letter- TPXW. I have seen TPMW's, and they do just as well as any other DLT3C. But these X's were clearly worse. There was a huge thread on amdmb.com about them, and all of them did rather poorly in comparison to other DLT3C's. One of the best Barton steppings was the AQUCA XPAW. Most that you see these days are AQXCA XPMW's, and they do not seem to do as well. IF you look on the Vr-zone lists of the best overclockers of both Bartons and T-Breds, the front pages are dominated by processors of several stock speeds, but almost all having their third letter as A's, B's and C's. I'll do some more searching, but for now that's the best I've got. Basically, I've been hunting down the 4 letter codes, and I can't draw any conclusions about any of the letters in it from own findings except for the third letters. TPMW's, UPMW's, VPMW's, WPMW's and XPMW's all perform the same, but an XPAW's seem to be better than XPMW's within the same processor type. All 1700+'s are xPMW's, so we can't say anything for sure about them, but within Barton 2500+'s, xPAW's appear to be better than xPMW's. The difference between A and M appears to be negligible at most, though, but the difference between an M and an S or X is rather large.

Not to throw you guys off, this is a really interesting revalation for me, about the third letter.

I wrote a thread yesterday when I got my new 2500+ Barton.

Odd stepping, never seen this before:



AQZEA 0327TPBW

First off, the AQZEA ive never seen before. Must be new. Then according to the third letter, B, this elludes to a high integrity. Correct?

Correct.
Thanks for that post Gautam.

Gautam said:

I'm not very much against OC Detective.

Click to expand...

OC Detective is great. He's very knowledgeable but you need info like you posted to argue that wafer quality seems to be connected to the third letter of the code.