AMD Stepping FAQ

[Robrowe]

your right My bad It is the 2700/2800 that I is in question and yes the internal bus is 333 but the machine bus will be at 166

[Micutzu]

Actually that is called external bus , and it's 166mhz DDR or 333 .

[Pinky]

I did a little research on this subject a few months back, and originally posted this at AOA (have since parted ways there)...

Here's a cut / paste of what I learned...

_________________________________

Revison ("Stepping") Codes
I tried to place these in some type of "best->worse" overclocking order, but only generalizations can be drawn based on charting being done by the overclocking commmunity.

XP1500+ AGKGA (10) AGOGA (8) AGKFA (6) AGNGA (4)
XP1600+ AGOIA (10) AROIA (9) AGKGA (8) AGOGA (7) ARKGA (6) AGNGA (5) AGLHA (4) AROGA (3) ARNGA (2)
XP1700+ AGOIA (10) AROIA (9) AGKGA (8) AGOGA (7) ANGKA (6) ARKGA (5) AGNGA (4) ARNGA (3)
XP1800+ AGOIA (10) AROIA (9) AGKGA (8) AGOGA (7) AKYGA (6) AGLHA (5) ARKGA (4) AGNGA (3)
XP1900+ AGNGA (10) AROIA (9) AGKGA (8) AGOGA (7) AGLHA (6) AGOIA (5) AGKGA (4)
XP2000+ AGOIA (10) AROIA (9) AGOGA (8) AGNGA (7)
XP2100+ AGOIA (10) AGOGA (9)

Tb2200+ AIRDA (10) AIRGA (9) AXGIA (8) AXDAD (7)


Click here (http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/24332.pdf) for more information (white tech-sheets from AMD) on revisions/"steppings".

As quoted by Rick York (AMDforums.com):


The five letters you are refering to are not stepping codes. They are process revision codes. The stepping is just one aspect of the process and there are very many (nearly a hundred.)

[Micutzu]

Ok , this looks very useful , i'll definetely use it to adjust my ranking . That link is not working right now .

[Pinky]

Originally posted by micutzu20
Ok , this looks very useful , i'll definetely use it to adjust my ranking . That link is not working right now .

the white sheets link works fine for me (at least that's the only link in my post...)

[Micutzu]

OK , now it's working , i'll look into it as soon as i find a little spare time .

[Pinky]

First thing to do is stop using "stepping" (took me months to break the habit once I learned "the truth" ) :p

[shroomer]

I agree the stepping is a guide there are many other factors that come into play when OCing IE: mobo,HSF,Case cooling,PSU,

If you use this guide then use it as that a guide not a etched in stone law :D

[fibonaccov]

Originally posted by danimal
my AGNGA 1800+ only got up to 1.68 GHZ
I guess it all depends on the factory - my AXP 1800+ (unlocked) does NOT wanna go above 1.62GHZ even at 1.85v vcore...

:(

AXP 1600 AGOIA is the one to get IMHO - very few surprises...

--fibo

[SycoraX]

Originally posted by fibonaccov

I guess it all depends on the factory - my AXP 1800+ (unlocked) does NOT wanna go above 1.62GHZ even at 1.85v vcore...

:(

AXP 1600 AGOIA is the one to get IMHO - very few surprises...

--fibo

Ya.. I feel ya bro... I can't get mine above 1.68ghz... Probably some ****ty stepping I have here... Oh well, maybe I should replace it with XP2600+... :)

[Robrowe]

there is another thread that has stepping in it and I cant remember where it is, just curiious to know who is right. I think this one but cant be sure

[mr_magoo]

i have an xp1800 agoga. is this any good for overclocking?? how much of an overclock do u think ill get on air?

[shroomer]

that should get 1.8 easy dood :D

[mr_magoo]

sounds good, to get it to a 1.8 would i need to unlock??

[shroomer]

nope should go there plus some locked and good cooling :D

[mr_magoo]

my coolings pretty good, do u think my motherboard or ram will stop me getting a good oc? have u got any tips before i start?

[shroomer]

Well if you can set the ram to 133 so it dose not go up with the bus that might help cuz that ram will need to go 157 bus with a locked cpu to get 1.8ghz

[Micutzu]

You'll get better results with a 1600+ though

[SycoraX]

Just checked my cpu stepping, it is AGOGA. I can't reach any more than 145FSB, is that normal for this stepping?

[fibonaccov]

Originally posted by SycoraX
Just checked my cpu stepping, it is AGOGA. I can't reach any more than 145FSB, is that normal for this stepping?

Dunno but my AXP 1800 AGOIA won't go above 142fsb *locked* - running at 9.5x168 which is better - now replacing by 1600 AGOIA - tested that sucker and going much higher now...I've unlocked it as well ! :)

[shroomer]

Originally posted by SycoraX
Just checked my cpu stepping, it is AGOGA. I can't reach any more than 145FSB, is that normal for this stepping?

1800 AGOIA what letter code Y 9 4 ?

[SycoraX]

1800 AGOIA? What do you mean? That's what I found on cpu:

AX1800D MT3C
AGOGA O2O2 RPBW

[shroomer]

What is the next line below that?

[SycoraX]

I am not sure, but I think it started with Y...

BTW, what difference does it make? Which one would o/c better?

[shroomer]

That code makes a big diferance but if it is Y that is one of the best ones So crongrats :D

[SycoraX]

Just checked it...again... :) It says Y7515040384.... Is it good?

[shroomer]

So it is a AGOGA Y week 02 of 2002 that is above average so I would guess 1.875ghz + maybe :D that is with good cooling and 2v + on the core :D

[SycoraX]

So why can't I get more than 1.668ghz? The computer either restarts itself or some crazy stuff starts going on when the FSB is on 146 mhz.

[shroomer]

Start a new thread on that topic in the Overclockers Hotline forum and more people can help on that issue :D i will reply there

[SycoraX]

Nevermind, I think i figured out what was wrong...lol... you can check my started topic in this this forum on that issue...

[Micutzu]

AGOGA's are usually better than AGOIA's on the XP1800+ and XP1900+ , but only on those .

[xMagusx]

Older stepping new to the guide ;) well i got a 1900+ that is an ARNGA - Y week 50 of 2001 i dunno where it would fall on the list .....likly somewhere around the AGOGA but im not sure :) someone wanna help? im currently in the process of unlocking :)

[Micutzu]

That stepping is pretty rare , i would place it between AGNGA and AGOGA , but i have very little info on it . Tell me how it does , i'm really courious .

[xMagusx]

will do

when i get my new ram from shroomer i shall test it unlocked ;) then ill attempt to unlock it again :P

[u4ikstilz]

Originally posted by micutzu20
AGOGA's are usually better than AGOIA's on the XP1800+ and XP1900+ , but only on those .

So how high should I expect from a 1900+AGOGA? Waterkit is on the way. I'm at 12x142 right now, but I think my ram and mobo has maxed out on memory speed cause of the 4:5 multiplier. I have corsair pc2700 and it's at 2x 178MHz (356MHz data rate) according to sandra. I doubt I could go any farther on memory, and what's the highest someone has gone on the Via KT333 chipset?

[erk417]

AGOIAs have a rediculous top speed that's very frustrating!!! Can't get it past about 1.65. These AMD steppings are ****ing me off!! No way around it except to fish around for an AGOGA.

[Micutzu]

Well the AGOGA can go up to 1.8ghz , maybe higher . You should definetely run the memory syncronised with the FSB , as PC2100 . You have almost no gain from the high RAM bus , since the FSB can't use it .

[JoJoDaClown]

I have a AVHAR thunderbird.... according to your list, if it's the same as the AVHA, I should be able to overclock this rather well... correct?

Here's all of it:

A1000 AMT3B
AVHAR 0106VPMW
K005987 1104
@ @ 1999AMD

Tell me everything.... please

[Micutzu]

Usually the ones ending in 'R' oc better than the same ones , but without the 'R' . In your case , AVHA < AVHAR .

[Drozdov]

micutzu, the RIWGA are not better than the AIUGA

[Micutzu]

Well they give about the same results as far as i've seen till now , i put it first because it's newer and it SHOULD oc better . Not enough data yet to make a precise ranking of those 2 .

[Drozdov]

AIUGA have been getting similar OC results but at a lower Vcore

[Drozdov]

and i wouldnt necessarily say its newer...my RIWGA is week 34

[Micutzu]

I'll look into it , but tomorrow , now i'm very tired .

[Drozdov]

ok, i have both the RIWGA and AIUGA tbred chips...ill see how the AIUGA performs

[Joey]

Steppings only affect the overclock factor right? (Determining what to do if I get an AGOIA 9!)

If it affects the actual performance of the chip, I'll use words as my helpers in getting a better one at newegg. (or at least try, never give up without trying...)

[Drozdov]

overclocking is right, not stock

[Micutzu]

Originally posted by Joey
Steppings only affect the overclock factor right? (Determining what to do if I get an AGOIA 9!)

If it affects the actual performance of the chip, I'll use words as my helpers in getting a better one at newegg. (or at least try, never give up without trying...)

It only affects the overclockability , and the heat generated (only a little) .

[dynetk]

It could be possible that the latest steppings will also increase performance. For example the Intel c1 cores are supposed to be slightly faster compared to an equal in mhz p4 of lesser stepping. Though they didn't mention any of this to the public :)

[Inferno]

What is it that the stepping of AMD cores specifies? What inside the core is changed when a new stepping is released? (What makes them overclock better?)