Short answer: There might be fryness.
Reason: P3's up to 1ghz were based on Coppermine core. Core voltage about 1.6 or 1.65v, .18 micron, etc. Intel tried making a 1.13ghz part based on the Coppermine core, and failed - they were recalled.
P3's over 1ghz are exclusively Tualatin core. Lower core voltage, slightly different pinout, and first generation i815E chipsets don't support them.
Sounds like, by using the "Up to 1ghz" wording your motherboard manufacturer says that only Coppermines will work...