Amd64 steppings and codes for info.

Question

You can find the 'core code' (sometimes refered to as the 'stepping code', though technically it's not a stepping in the true sense of the word, but can indicate the stepping) located on the heatspreader or underneith the heatspreader on a black label at the edge of processor. Should look something like:
ADA3400AEP5AP
AAALC0341MPMW
F447141J30044
Here is a brief guide to understanding these 3 lines of code on AMD processors:
ADA3400AE5AP - 1st line
ADA ----- ADA = AMD A64 Desktop, AMA = AMD A64 Mobile DTR, AMN = AMD A64 Mobile
3400 --– model number or performance rating (PR)
A –------- package type (A =754pin Lidded OuPGA, B=754pin Unlidded OuPGA, C=940pin Lidded CuPGA)
E –------- default voltage (C=1.55v, E=1.50V, I=1.40v)
P –------- max case (heatspreader?) or die temp (O=69oC, P=70oC, X=95oC)
5 –------- L2 cache (3=256KB, 4=512KB, 5=1MB)
AP –----- core stepping (AK=C0, AP=C0, AR=CG, AT=CG, AX=CG)
AAALC0341MPMW - 2nd line
AAALC is the 'core code'. As a general rule when comparing 'core codes' that have the same starting letter (ie A), then the higher up the alphabet the other letters are, the better it is. Thus AAALC should be better than AAAHC.
0341, the 4 numbers after the core code refer to the date of manufacture. The first 2 numbers refer to the year and the second 2 numbers refer to the week. In the above case 03=2003 and 41=week 41. Generally the newer the processor the better it should be. So you might find a week 41 AAALC that overclocks better than a week 34 one. Though some weeks tend to be better than others, so it's not always true.
MPMW, supposedly one user claims that in the 'WPMW' code, the letter M (ie the 3rd letter) refers to the batch or wafer. Supposedly the lower this letter, the better. Another user agreed and cited that they had seen and XPAW do very well, XPMW do averagely well and TPXW do worse than average. Some cited a AMD T-Bred B datasheet as pointing this out. Even saying that if it's A, B, C they are early batches of the week and good. But if they are an 'M' it could refer to combined lots from many batches that needed to be rated lower. Plus others like R, I, S, and even digits like 1 to 9, with it being suggested the numbers are worse lots than the letters. However, another user also seems to think this 3rd letter is somehow related to the to default vcore or threshold voltage required to run at stock speeds and that the higher the letter, the better.
F447141J30044 - 3rd line
The third line has been suggested as stating the production line (first character, ie F) and some kind of batch and serial number identifier (ie 447141J30044). Certainly the first character of the third line in the past with Athlons, has been used suggest good overclocking cores. Ones with letters (Y, K, etc) would seem to overclock a bit better than ones with numbers (9, 7, etc). Y's used to be the best overall, though this was only noted by studying T-Bird Athlons. No study has been done to see if this holds true with AthlonXPs, so most only go by 'core code' and date of manufacture now.
Noticed a comment about some seem to think the last 4 digits (ie 0985) refer to the cores number in that batch and that a lower number is better (one user claims anything 0150 or below is very overclockable). Maybe could be related to the location of the core on the silicon wafer, lower number means closer to the centre. In theory, cores made from the centre of the silicon wafer are of better quality than cores made on the outer edge. However, no proof to back up such theory as yet. Infact one user claimed with their two same stepping AthlonXPs, the 0112 one overclocked better than the 0014 one.
The C0 stepping. Voltage is 1.50v for desktop and 1.40v for mobiles. This stepping can be identified by the following 2 letter code at the end of the OPN (ie ADA3400AEP5AP) and by CPUID:
A64 Desktop ---: AP (CPUID F48h)
A64 Mobile -----: AP (CPUID F48h)
A64 FX -----------: AK (CPUID F58h)
Thus:
A64 3000+ -----------: ADA3000AEP4AP (512k, 1.50v, C0, F48h)
A64 3200+ -----------: ADA3200AEP5AP (1MB, 1.50v, C0, F48h)
A64 3400+ -----------: ADA3400AEP5AP (1MB, 1.50v, C0, F48h)
A64-M 3000+ DTR ---: AMA3000BEX5AP (1MB, 1.50v, C0, F48h)
A64-M 3200+ DTR ---: AMA3200BEX5AP (1MB, 1.50v, C0, F48h)
A64-M 3400+ DTR ---: AMA3400BEX5AP (1MB, 1.50v, C0, F48h)
A64-M 2800+ ---------: AMN2800BIX5AP (1MB, 1.40v, C0, F48h)
A64-M 3000+ ---------: AMN3000BIX5AP (1MB, 1.40v, C0, F48h)
A64-M 3200+ ---------: AMN3200BIX5AP (1MB, 1.40v, C0, F48h)
A64 FX-51 -------------: ADAFX51CEP5AK (1MB, 1.50v, C0, F58h)
As for overclocking results (some claim the Brown ones overclock better than Green ones, but unsure):
AAALC 0337MPM @ 2621MHz w/ 1.7v (Mach I)
CAAMC 0339WPMW 9446548130306 @ 2500MHz (aircooled)
CAAMC 0339XPMW Brown @ 2540MHz w/1 95v (Chilled watercooled)
CAAMC 0342 @ 2655mhz (up to 2.0v?) (chilled watercooled, -20oC)
CAAAC 0345RPMW @ 2440MHz w/ 1.7v (watercooled)
CAAAC 0345 @ 2.6GHz w/ 1.8v (Mach I)
CAAMC 0349 RPMW @ 2400MHz w/ 1.6-2.0v (unstable)
CAAOC 0350 XPMW @ 2600MHz w/ 1.85v (watercooled)
A64 3000+ 'AP' CAATC 0350XPMW @ 2508MHz w/ 1.65v
A64 3000+ 'AP'? CAAOC 0352 @ 2704MHz w/ 1.92v
A64 3000+ 'AP'? CAAOC 0352 XPMW Brown 2.5GHz w/ 1.85v
A64 3200+ 'AP' @ 2.8GHz w/ 1.9v (dry ice)
A64 3200+ 'AP'? CAAOC @ 2.5GHz w/ 1.66v (stock aircooled)
A64 3200+ 'AP'? @ 2830MHz w/ 1.9v (triple cascade, -46oC)
A64 3200+ 'AP'? @ 2608MHz w/ 1.68 (Mach I)
A64 3200+ 'AP'? @ 2756MHz w/ 1.8v (Mach II)
A64 3200+ 'AP' CAACK 0330UPWM 9438245200435 @ 2380MHz w/ 1.7v (stock aircooled), 2500mhz (Mach I)
A64 3200+ 'AP' CAAKC 0334TPMW 9441535240131 @ 2400MHz w/ 1.64v, 2450MHz w/ 1.71v (stock aircooled)
A64 3200+ 'AP' CAAMC 0339WPMW 9446635J30492 @ 2.5GHz w/ 1.7v (watercooled)
A64 3200+ 'AP'? CAAMC 0339WPMW 9 0072 Green @ 2.36GHz w/ 1.7v (stock aircooled)
A64 3200+ 'AP'? CAAMC 0339WPMW 9 Green @ 2609MHz w/ 1.77v
A64 3200+ 'AP'? 0341 Brown @ 2767MHz w/ 1.88v (Mach I)
A64 3200+ 'AP' CAAAC 0345SPMW @ 2750MHz w/ 1.904v (Mach I)
A64 3200+ 'AP' CAAMC 0347VPMW 9359625k30176 @ 2349MHz w/ 1.65v (watercooled)
A64 3200+ 'AP' CAAOC 0351 9 0160 @ 2.7GHz w/ 1.9v (Vapochill PE)
A64 3400+ 'AP'? @ 3.0GHz (Mach I w/ R404a) - in 3DMark 400-500 points behind FX-51 (@ 3.0GHz?)
A64 3400+ 'AP'? @ 3.1GHz w/ 2.04v (Cascade)
A64 3400+ 'AP'? @ 2.75GHz w/ 1.7v
A64 3400+ 'AP' CAAOC 0350XPMW 9832334L30188 @ ~2.5GHz w/ 1.7v (stock aircooled)
A64 3400+ 'AP' CAAOC 0351XMPW @ 2.8GHz (Mach II)
A64 3400+ 'AP' CAATC 0351XPMW @ 2784MHz w/ 1.7v
A64 3400+ 'AP' CAAOC 0352TPMW @ 2821MHz w/ 1.7v, 2929MHz w/ 1.8v (Mach II w/ r404a)
A64 3400+ 'AP' CAAOC 0401SPMW 9839644A40514 @ 2508MHz w/ 1.7 v (stock aircooled)
A64-M 3400+ DTR 'AP'? @ 2920MHz w/ 1.85v (Mach II)
A64 FX-51 'AK' @ 3009MHz w/ 1.728v (Chilled Ethanol, -65oC)
Some commented they have seen quite a few CAAOC 0352XPMW all do at least 2.4GHz on aircooling. Plus between week 0351-0352 supposedly are good cores, along with XPMW ones. They cite their A64 3400+ XPMW doing 2.6GHz on aircooling.
The new CG stepping, has a few tweaks including energy saving, memory compatibility and performance. Still 1.50v Vcore for desktops and 1.40v for mobiles. It has been suggested all the initial S939 processors will be CG stepping. Infact there are actually 3 CG steppings SH7-CG, DH7-CG and CH7-CG. Again, these stepping can also be identified by the 2 letter code at the end of the OPN (ie ADA3400AEP5AR) and by CPUID:
A64 Desktop ---: AX (DH7-CG, CPUID FC0h), AR (SH7-CG, CPUID F4Ah)
A64 Mobile -----: AR (SH7-CG, CPUID F4Ah)
A64 FX -----------: AT (SH7-CG, CPUID F5Ah)
Thus:
A64 2800+ -----------: ADA2800AEP4AX (512k, 1.50v, DH7-CG, FC0h)
A64 3000+ -----------: ADA3000AEP5AX (512K, 1.50v, DH7-CG, FC0h)
A64 3200+ -----------: ADA3200AEP5AX (512K, 1.50v, DH7-CG, FC0h)
A64 3000+ -----------: ADA3000AEP4AR (512k, 1.50v, SH7-CG, F4Ah)
A64 3200+ -----------: ADA3200AEP5AR (1MB, 1.50v, SH7-CG, F4Ah)
A64 3400+ -----------: ADA3400AEP5AR (1MB, 1.50v, SH7-CG, F4Ah)
A64-M 3000+ DTR ---: AMA3000BEX5AR (1MB, 1.50v, SH7-CG, F4Ah)
A64-M 3200+ DTR ---: AMA3200BEX5AR (1MB, 1.50v, SH7-CG, F4Ah)
A64-M 3400+ DTR ---: AMA3400BEX5AR (1MB, 1.50v, SH7-CG, F4Ah)
A64-M 2800+ ---------: AMN2800BIX5AR (1MB, 1.40v, SH7-CG, F4Ah)
A64-M 3000+ ---------: AMN3000BIX5AR (1MB, 1.40v, SH7-CG, F4Ah)
A64-M 3200+ ---------: AMN3200BIX5AR (1MB, 1.40v, SH7-CG, F4Ah)
A64 FX-51 -------------: ADAFX51CEP5AT (1MB, 1.50v, SH7-CG, F5Ah)
A64 FX-53 -------------: ADAFX53CEP5AT (1MB, 1.50v, SH7-CG, F5Ah)
Cool'n'Quiet feature has changed with the CG Stepping. So instead of the previous powering saving state of 800MHz and 1.30v (35W TDP), the CG stepping can manage 1.0GHz and 1.10v (22W TDP). The A64 3400+ also gets an extra power saving state too, 1.8GHz and 1.30v. There is also reduced requirements for AMD64 interface logic energy consumption.
The CG stepping is also meant to bring better memory performance via a "2T memory timing" that allows for higher density or frequency memory. It should also improve memory compatibility by no longer requiring identically paired modules for the 2nd and 3rd slots with 3 dimm slots.
However, some claim the CG Stepping is slightly slower than the C0 stepping. Though, there are some C0 vs CG benchmarks seeing how different memory config and timings effect things. With 1 module no real difference. 3 mixed modules the CG works, the C0 doesn't. With 3 identical modules C0 doesn't work with 2.5-3-3-7 but the CG did. At CL3-3-3-7 the CG is clearly a bit slower than the C0, but not much. Comparing CG 2.5-3-3-7 vs C0 CL3-3-3-7, you find some benchmarks (inc 3DMark) the CG is slightly faster and some the C0 is slightly faster, though both end up with same SuperPI 1M time of 44s.
As for overclocking results:
A64 3000+ 'AR' SH7-CG CAATC 0350XPMW @ 3.0GHz w/ 1.968v (r22 phase change)
A64 3000+ 'AX' DH7-CG CBAPC 0404VPFW 9847235B40119 @ 2.4GHz w/ 1.68v (1.65v in BIOS) (stock aircooled)
A64 3000+ 'AR' SH7-CG CAATC 0404XPMW 0256 @ 2655 w/ 1.9v (watercooled)
A64 3000+ 'AX' DH7-CG CBASC 0406UPMW @ 2.6GHz w/ 1.67v
A64 3200+ 'AR' SH7-CG CAAPC 0408TPMW 9561925C40400 @ 2.5Ghz w/ 1.7v (watercooled)
A64 3400+ 'AR' SH7-CG CAAPC 0408TPWM 9567014C40733 @ 2.7GHz w/ 1.7v (Mach I)
A64-M 3200+ DTR 'AR' SH7-CG @ 2508MHz w/ 1.74v (1.7v in BIOS) (aircooled)
A64 FX-53 'AT' SH7-CG @ 3423MHz w/ 2.096v (Triple Cascade, -112oC)
A64 FX-53 'AT' SH7-CG CAABC 0410MPMW @ 3404MHz w/ 1.987v (LN2)

Answer 1

Nice work dude!!!
I say its a sticky