The machine in my sig named Thesenuts is running an XP2500...

2340mhz @ 1.9v
Epox 8K5A2+ Mobo (KT333)
SLK-900U Heatsink + Akasa 80mm fan

I don't remember the stepping but it's an early one - I bought this chip as soon as they were available. It was bought in Belgium. I have not tried it on the prometia yet but think it might actually run better than my xp3000+ since it goes a bit faster than the xp3000+ on air. The xp3000 does 2.8ghz on the prometia.