29 Feb
2008
29 Feb
'08
4:46 p.m.
At 9:26 -0600 2/29/08, Dave wrote:
Interesting idea.... I've worked with chips that had connectiosn for
decoupling capacitors for particualr secitons in the chip (the most
ovious being the Transputer which needs a 1uF capacitor between 2 of its
pins to decouple the clock multiplier PLL). In general, these components
are not conencted to a power line or ground other than through the chip.
I have no idea if the VAX 2000 chips are like this, but if they are, then
a leak in one of those cpacitors would certainly cause thigns to run hot.
-tony
Yes, I'm wondering if it's something like
that, however how likely is it
that both devices would experience the same fairly-uncommon failure mode
at the same time?
I'm chiming in very late and probably not very helpfully, but is
there any way a decoupling cap in the vicinity of the FPU/CPU could
either load them or generate heat itself by beginning to short to
ground? My only VAX (4000VLC) had a fault like that in the reset