Nice OC..post a WCPUID pic or something...what type of cooling you have??...1.81 Ghz is quite the OC from a 1500+...and are you running softfsb to get that FSB speed?
sorry to be asking all the questions...but i have NEVER seen a 1500+ do 1.81 Ghz..thats pretty amazing
[EDIT: According to the CPU database..there are 5 entries over 1.8 Ghz...4 of them are believable i guess..1 of them says 2.5Ghz...***coughcoughbullsh*tcoughcough***
Nice overclock!!]