18 Apr
2005
18 Apr
'05
12:59 a.m.
Heinz wrote about the PDP-11/55:
claimed that it was the fastest PDP11 of
the blinkenlights
machines made by DEC.. Is that true?
With bipolar memory, the 11/45 or 11/55 are definitely the fastest
DEC machines with "real" front panels.
I expected an 11/70 to be instruction for
instruction faster
No. The cache was roughly the same speed as the bipolar memory of
the 11/45 or 11/55, but main memory was slower. And access to Unibus
was slower.
How about compared to a 11/70 with a PEP70 instead of
factory memory and
cache?
With PEP70 (replaces DEC main memory) it should be faster. With PEP70 and
HC4x Hypercache (replaces DEC cache) it should be much faster.
With QED95, even faster yet. But is it still an 11/70 at that point?
Eric