Re: Defective DRAM chip? Max ns speed?

[spec@vax2.concordia.ca (Mitchell Spector)]

In article sirius@spirit.com.au (Michael Hickey) writes...
>
>The speed of memory chips can never be too fast (I think)  On a IIgs you
>should never go SLOWER than 120ns or possibly 150ns (if you can get new
>chips this slow I'd be amazed).  Don't spend any extra $$ getting faster
>than 80ns chips.  It's a waste on a "slow" computer like the IIgs.

   All that is required are (at least) 150ns DRAM chips, and of course
that they use CAS-before-RAS refreshing. Anything faster is basically 
wasted on a IIgs, the chips may move things around quicker, but it still
has to wait around for the system to catch up.
	 
>I always try to match same-speed chips in the same bank for aesthetic
>purposes.  Others may have good technical reasons for doing this.

   Unless I'm mistaken, it shouldn't matter. In the past, I had quite
an interesting mix of brand and speed DRAM chips in my Apple memory 
board (150ns, 120ns, 100ns). It worked just fine for years.

>                 Michael Hickey, Canberra, Australia
>         |
>       --x--     sirius@spirit.com.au
>         |

Mitchell Spector
spector@vax2.concordia.ca