Okay I think this is probably unlikely but can you
put a PIII into a PII slot. I have a Chaintech mobo,
which I think supports max cpu speed of 450Mhz.
Yes, you can always put a PIII into a PII slot. Since your board supports the PII 450, it has at least the 100MHz bus option, which means that you can support at least the PIII 600 Katmai, which is the earlier 512k version. The later Coppermine version, which has 256k cache (but running at full speed), may or may not be supported depending on your motherboard's voltage support.
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