Partially-bad chips; was: repairing early HP calcs

[Gordon JC Pearce]

Chuck Guzis wrote:

> Back in the days when DRAM was precious, Intel had some "8Kx1" DRAMs that
> were really "half good" 16K parts.  You used the "-x" digit to determine
> which half to use.  I don't know if these were in general circulation, but
> the sales engineers were passing them out to customers working on designs.
> I may still have one or two kicking around that I found actually had 16K
> worth of usable bits, providing they weren't run too fast.

The ZX Spectrum actually has jumpers on the board to specify whether 
you're using "top half bad" 32Kx1 or "bottom half bad", for the upper 
32k.  Of course the ones that always went were the bloody awful 4116es.

Gordon