Asus P55SP4 - Manual (Page 28)

upgrade Guide
Module Sockets & Orientation
Cut-out
nmnmmnnnmnnnnnmmnn.r-s:nmnnnnnnnnnmnnnnnnnnnn
SIMMs have a cut-out at one end that matches an
extension on one of the vertical posts of each socket.
SIMM# 1
i 7
I
iI
2 3 4
3
PK
% CtK
Put orientation cut-out at this end.
Remember; Modules must be installed in pairs, in sequence and
must meet all the required specifications and be the same speed.
The only exception is that you can install a single module larger
than 2MB in socket SIMMl, with the other sockets empty.
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