>> Thanks for the answer.  So it sounds like one can then buy the dual
>> processor card and a 9600 uniprocessor and just swap them, right?
> Exacly. Too bad dual G3 or G4 cards are still way overpriced.

are there dual G3 or G4 cards for those machines?

> On the other hand - you may want a cheap (single CPU) G3 card with big 
> and fast L2 cache instead. The 604es have the better FPUs but they're 
> seriously hampered by the slow bus ( max. 50MHz -> 400MB/s ), even 
> more so if you have two of them - they share the same bus, so for 
> anything that's not purely CPU-bound you'd be better off with a G3 - 
> the fast L2 cache vastly improves things. In a 9600 you can use a 
> 604ev with L2 cache on the CPU card though, this combination would be 
> even better than a G3 I guess, but you can get G3s at 500MHz and more 
> while the 604s max out at about 300MHz ( the fastest ones IBM used ran 
> at 375MHz but I've never seen or heard of a Mac with a 604 faster than 
> 300MHz )

german company 'Phase 5' (well-known Amiga player, but bankrupt end of 
the 90's) produced 375MHz 604 cards for those machines...

>> Next stupid question.  The 7300-8600 systems all seem to have
>> interchangeable processors right?
> Most do - see everymac.com for a comprehensive reference.
>
>>  If so, does that mean that one could stick a 9600 dual processor 
>> board in say a 7300?
> Yes and no. The 9600 had a slightly different CPU slot so it could use 
> 604ev boards, these won't work in other Macs. Most CPU cards that work 
> in a 7300 should work in a 9600 though.
>
>> And no, I wasn't expecting MacOS to run on the resulting system :-)
> You'll want to run -current, it has some serious bug fixes / 
> improvements over 2.0, mainly in interrupt handling.

-- 
Timo Schoeler | http://macfinity.net/~tis
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