Hi!
Overclocking your CPU should not cause any problems with the Mediator, my Blizzard 060 is overcloocked to 72mhz and my Mediator is running fine.
A limitation you may have is the ram module/s so get yoourself decent 50ns Simm/s.
My CPU is the latest revision and does not even need a fan at that speed although most of the time I run it at 66mhz which I find more stable with my 60ns 128mb Simms.
Even if you have an earlier revision 060 you may still be able to overclock and use a cooling fan.
Stachu100 is the man to speak to when it comes to overclocking these cards, he would be able to change the CPU and fit a socket for the oscilator so you can swap it out easily.
Stan done the work on my Blizzard PPC and it runs perfect :afro:
Steve.