How to overclock a SPARC CPU

The following describes a procedure to make a SPARC CPU run faster than its set speed. I personally do NOT do this on any machine I care about, and can make absolutely no verification of how well it works, or any risks it may pose to the hardware. The only time I have witnessed this done was on a 300-MHz Ultra-II, which was able to be overclocked to around 350-MHz. I forget whether attempts to go higher stopped at the 350-MHz limit, or simply had no effect.

You will need to be at the eeprom's 'ok' prompt.

ok nvedit
   0: also hidden
   1: d# 123 at-speed       (...where 123 is the speed you want, in MHz)
   2: <Ctrl-C>
ok nvstore
ok setenv use-nvramrc? true
ok reset-all

To read the CPU clock speed:

ok .speed

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