I can also comment on that these cpu's are really hit or miss, for example in the last 3 days I have tested 3 AIUHB 2100 xp cpu.

The first one was 03-01 and did fairly well at 2075mhz at default voltage, I was gonna keep this one then came across 2 more 2100's dated 0302, tested these and the first one hit 2175mhz rock solid stable (prime stable) at default voltage while the other needed 1.75 volts just to hit 2.1 ghz, and these were from the same batch / week, so really the secret lies in being able to test multiple cpu's and selecting the right one

I'm lucky enough to be able to bench test almost any hardware I buy, so for ordering online or just buying from a small reseller, it's really luck that will hit you a decent AMD cpu.