Shape doesn't seem to be a good identifying factor.
Yes, the square core is the palamino. No question.
Yes, the rectangular core is the tbred. No question.
Yes, the longer rectangular core is the Barton.
I have 2 athlon based systems at home for my personal use. An 1800+ and a 2100+. Neither of them do I care to open and pull the processor to just check.
Instead, because I work on alot of computers and I don't always feel inclined to pull the cooler off and examine the core, I choose to use a different method to identify them, hence, I went and got the *AMD* specific cpuid program.
I will go check for the wcpuid program and look at the values.