Athlon/Thunderbird?? Questions for the class!

[Spidey]

Ok, here goes.
I found an Athlon 1.2 giger and my local shop. It's oem and the numbers are AXIA0119MPM.
Now, is this classed as a thunderbird? Is there a difference in L1 and L2 cache size. Which ones have 512 and which ones have 256?? The cpu I have on hold is a 266fsb which will work just peachy in my A7V133.
I guess my question would really be, what different kinds of Athlons are out there and what are the differences between them.
I have searched around the web and have found bits and pieces, but just enough to be-fuddle myself!
Thank you kind sirs!
Clock on!

[Rob Cork]

All socket A 'athlons' are actually the new Tbirds - they have 256K cache 'on-die'. The old slot-A athlons had 512K cache, which was slower because it resided on the pcb rather than the actual cpu die itself. So - all tbirds have 256K cache, and all socket A 'athlons' are Tbirds. Easy? Nope, confusing as hell to start off with - the problem is AMD still refer to Tbirds as athlons (but 'athlons with on-die cache'), tbird was just the codename but people picked up on it. Oh well, you get the idea :)