Re: G3 upgrade L2 cache

[John Klos <john%ziaspace.com@localhost>]

> > I think the crescendo PCI was for the Macintoshes with
> > non-replaceable CPU's - you could plug them into a free PCI slot and
> > disable the onboard CPU.  If I remember correctly the 6400 was such a
> > beast.

That card which goes in a PCI slot was only for the PowerMac 7200. 
Accelerators for 6400s and others were cards which were installed into the 
motherboard's L2 cache slot and "took over" the CPU.

> My card is not such a device.  The basic finger spacing and overall
> connector size is about right for PCI, but it is definitely not plugged
> into a normal PCI slot, and could not work in a normal PCI slot.  When
> I pulled it, I saw a wide band of copper at the edge of the card -
> about the bottom half of the socket, I'd say - that ran clear across
> the connector.  If plugged into a PCI socket (if it even fit
> mechanically, which it might not - I didn't compare it in detail) that
> would short all the pins on one side together.  I think there was a
> similar band on the other side, but I'm not sure of that.

No, the Crescendo PCI is a processor card intended for PCI Macintoshes 
(7300 - 9600).

> I'm beginning to wonder if this card has fried cache, or maybe the
> clock divisor of 2:1, while right for the Crescendo PCI, is wrong for
> this card.  I tried write-through L2RAM_FLOWTHRU_BURST and it wedged
> hard right after printing the cache status line (the same place the
> other failures failed).

That's entirely possible. You could just try a much slower multiplier 
(like 4:1) and see if the cache will work at all.

> There are only 21 possibilities (assuming the 512K size is right, and
> since that came from the card's sticker I'm fairly confident of it).
> Trying them all is not out of the question.

True. Even if the L2 is fried, it's still not a slow processor.

John