I got this email yesterday:
I just returned from my local computer fair (here in England/UK). The only low speed Tbred Bs I saw were XP1800+, but they were
I have good eyesight to read the labels – the vendor had 3 of them all the same. I read the labels 3 times!! That week 39 (year 02) is really interesting (and I didn’t buy one)
Seems to me reasonable to speculate that the J stepping XP1800s are reject XP2400 (or whatever) especially if as long ago as week 39 they were tumbling off the production line.
(And no, the UK is not that backward – I did see some week 0251 boxed processors – higher speed than XP1800 and I did not buy cause of price.)
A week 39 chip would be one made at the very end of September.
In contrast, the first reference that these chips would be made was found at XBitLabs on December 6.
Given that AMD chips have been getting to people within two-three weeks of manufacture; this is an indicator that the decision to come up with low-breds was a matter of need, not choice.
The lower performance of even recent “J” chips indicates that AMD’s speed bins for the TBredBs haven’t been all too good (though good enough for now).
This could change, but for now, I think you have to treat chips beginning with “J” as Just not good enough for high-end overclockers.
There is nothing wrong or evil with AMD selling these chips; I’m sure they work perfectly fine at their rated speeds, and that’s 98-99% of AMD’s market.
These chips are supposed to be the next Durons, anyway, so AMD can end up with plenty of these for some time to come with no problem.
What would be wrong is you buying one. At least AMD is nice enough to provide an indicator that these aren’t primo chips. You ought to take advantage of that.