Is my Cyberstorm PPC dead?

[amigakit]

Run WhichAmiga? program - what Mhz rating does the PPC show as?  Random values everytime can indicate a problem.

[amigakit]

Not necessarily- thats a good sign that it originally identified itself correctly.

233mhz CyberstormPPC cards have an infamous low tolerance to heat- have you tried the WarpOS patch:

Change ENVARC:PowerPC/No233Fix to 0      (enables patch)
Change ENVARC:PowerPC/No233Fix to 1      (disables patch)

Restart Amiga.

Of course extra cooling is preferable- the standard 5v fan may need upgrading to a 12v variety.

Also make sure that there is sufficient (+not too much) thermal compound between the PPC and heating and the fan is clean and rotating well.