i'm going to assume you mean what the numbers on a tbird serial mean
here's mine:
A1100AMS3B
AVFA0051CPDW
94438560315
first line:
A- Family architecture, in this case Atlon
1100- CPU speed, 1100mhz
A- package type, PGA
M- operating temp, M=1.75v and P=1.7v
S- case temp, S=95C and T=90C
3- L2 cache, 3=256kb
B- max FSB, B=200mhz C=266mhz
second line:
0051 refers to the week, in this case a week 51. i have no clue what the letters around it means
third line:
serial number of the chip
if you're looking for OC numbers, check out the
Overclockers Database