Processor and processor core

Guys...

Hows it going???

I have been going through the hardware spec of IBM system p systems.. and here i am confused

for IBM Power 520 Express it says

Processor cores:

One, two or four 64-bit 4.2 GHz POWER6 with AltiVec� SIMD and Hardware Decimal Floating-Point acceleration

now my question is

  • is 1/2/4 the number of processors that 520 can have each of 4.2 GHz?

                                 or
    
  • is 1/2/4 the number of cores per processor giving effective 4,2GHz speed. in that case, how many processors can 520 have to the maximum?

Regret if am not clear.. ready to explain if required

hi,
a Power 520 is available with 1 or 2 or 4 cores of each 4.2 GHz. (so max. 4 cores operating at 4.2 GHz each)
(IBM Power 520 Express specification summary)