I purchased 2x8 MB 72-pin (60 ns) SIMMs for my Quadra 800 from Chip
Merchant (I've been very satisfied with them in the past).  Either one
alone works, but both together fail.  I called Apple for advice and was
told that there was a problem with "Composite" SIMMs.  Only non-composite
SIMMs should be used with the Q-800.  Chip Merchant confirmed that they
presently sell only composite 72-pin SIMMs.  So, Q-800 SIMMs need to be
both 60 ns and non-composite.

Marty Sachs
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