Any advantage overclocking a g4 400mhz? or not worth.

I didn't notice any difference between 400mhz and 450mhz. You can sometimes get lucky and push them up to 500mhz but no higher.

> Any advantage overclocking a g4 400mhz?

As usual: If you overclock by x percent CPU bound tasks will take only 100/(100+x) of the time.

Could owners of MDD or FW800 with stock dual CPUs running at 1.42GHz let us know what temps the CPUs are running on startup and after say 10min?

I have done service on the Power Mac that I purchased recently, including reapplying thermal paste. I used Arctic Silver. I'm getting temps stabilised at about 56 deg C. It seems a bit too high (given that 62 is the max) but then it will take a few hundred hours for the paste to cure. Should I be worryed?

Also, this probably means no overclocking for me until CPU does the time

It's about 61,62 deg C. with proper heatsink and Verax cooling system.