[rescue] identify SGI cpu

[Scott Quinn]

> > I have a cpu saved and pulled from an Indigo 2 (I believe).
> >
> > It is an R4K class CPU.
> >
> > Part number on the bottom is 030-8232-001
>
> Haven't found the P/N (looks like even SGI doesn't know what
> it is), but I guess it's the rare R4k/250/1M, got pics?

No such beast exists- the R4400/250 had 2MB cache.

What you want to look for on the bottom of the processor module is the 
PM number

(e.g. PM1, PM2 ... PM5,)

PM1 = R4000/100
PM2 = R4400/150 (both these will work in an Indigo, higher ones won't 
(CPU voltage drops from 5V to 3.3V above this frequency)

PM3 = R4400/200
PM4 = R4600/133 (? not positive)
PM5 = R4400/250/2MB SC
PMT = R8000/75
PMT5 = R10000 at 175 or 195MHz.
PM6 = R4400/175
PM7 = R4400/200/2MB SC

Quick Indigo compatibility check- if the circuit board extends beyond 
the big aluminum heatsink it's not a PM2 and can only be used in an 
Indigo2 (unless it's a PM1 100MHz R4000, as that doesn't use the same 
heatsink. The board will still be square, though, rather than 
rectangular). If the board has some exposed memory chips, then it's a 
2MB SC module, either 200MHz or 250MHz. If the heatsink has a fan, then 
it's a R10k module.