On 12/05/2015 01:49 PM, Robert Jarratt wrote:
As the 5V seems fine, the ripple seemed to be about 20mV
(although I am going to check again), I do wonder what
could be causing the memory modules to appear to be
failing. I am hoping that re-seating will cure it. Regards
Rob
I ran a uVAX-II for 21 years here in my house. It was HOT
STUFF when I first got it in 1986! By 2007, it was the
slowest computer in the house. It ran continuously during
that period (at the end, it was only running a home
environmental monitoring program, or I would have shut it
down earlier.)
Anyway, after some years of flawless operation, I started
getting crashes every couple months. When it would hang, I
would power down and re-seat all the boards. It seems like
it was usually a failure of one of the grant chains (either
interrupt or DMA) and the disk controller would not be able
to transfer. Every once in a while I'd pull all the boards
and vacuum out the backplane and gently vacuum off the
boards. That sort of helped, maybe.
The external UVII memory also had ribbon cables across the
boards. Rough handling of these cables can cause intermittents.
Jon
