11/45 hack?

[Eric Smith]

On Sun, Feb 8, 2015 at 2:16 AM, Paul Anderson <useddec at gmail.com> wrote:
> Think of the bipolar as very fast extra memory. It can sort of act like a
> cache memory, and can help with processor throughput.

Only if software is carefully written to use it that way. The hardware
doesn't use it in any way similar to a cache.  It's just a memory
region that happens to be fast.

> I thought there were
> 2 controller boards and 4 G401s, but one is better than none. You can check
> that on the top of the processor box in the module chart.

Depends on how much Fastbus memory you have.  There's a controller in
slot 16 for memory modules in 17-20, and optionally a second
controller in slot 21 for modules in 22-25.  There's no interleaving,
so you only need the second controller when you have five or more
memory modules.