Date   : Sun, 12 Jun 2005 13:05:33 +0100
From   : Mike Tomlinson <mike@...>
Subject: Re: Issue 4 BBC B's

In article <E14E4ED61DD1D41195B70002A52C476D0AA95ED2@...
2.dera.gov.uk>, Littlefield Aaron <CALITTLEFIEL@...> writes
>
>Hi everyone,
>
>Could somebody please explain to me why issue 4 model B motherboards were
>updated to 7? I've heard rumors that they were prone to overheating but I
>don't know the truth on this. Just interested to find out if anybody knows
>anything about it.

Changes from iss 4 to iss 7 included some thickening up of tracks on the
board to improve power distribution.  The Video ULA was also changed
from a Ferranti chip requiring a heatsink to a VLSI unit, which didn't
need a heatsink, at about the same time.

Mike