I just bought a sawtooth G4 500 and want to upgrade the cpu. I have narrowed my choices down to 2 upgrades from powerlogix. first is a G4 1.6 with 512k L2 and no L3. the other is a G4 1.4 with 256k L2 and 2MB L3. the 1.6 is 269 and the 1.4 is 259. is the L3 worth going down 200mhz? this is my main concern.