Unlocking 2800+ Barton multiplier

In the Tom's Hardware article about the 3.06GHz P4 VS. the XP 3000+, it said that the XP 3000+(13 x 166=2.16GHz), once the multiplier was unlocked, could remain stable at 15 x 166=~2.5GHz. The article also mentioned that Barton CPUs overclocked well.
I have an ASUS A7N8X and 512MB TWINX CORSAIR XMS PC2700 LL. I am ordering an Athlon XP 2800+ Barton core, and have Artic Silver 3 and a Volcano 9 for it. I want to unlock the multiplier to get some more MHz out of the CPU, but have surfed the net and haven't found info about someone OCing a 2800+.
My question is, has anyone unlocked the multiplier on a XP 2800+ (12.5 x 166 = 2.08GHz)? If so, how high of a stable multiplier were you able to get? Actually because the XP 2800+ is still in the 5x thru 12.5x multiplier range, I'm not sure if unlocking the multiplier will give me higher #'s, unlike the 3000+ (13). Any info on the subject would be greatly appreciated.