Sony PCV-RX670 - Manuel (Page 60)

VAIO Digital Studio System Reference Manual 48
Memory Module (DDR-DIMM) Slots
Both sides of each Double-data rate, Dual Inline Memory Module
(DDR-DIMM) look very similar. The side with pin 1 has a small "1" to the
left of pin 1. Be sure to orient the memory module correctly in the
DDR-DIMM slot (a small triangle on the slot indicates pin 1).
DDR-DIMM1 DDR-DIMM2
Indicates pin 1
Memory module (DDR-DIMM)
1 1 1 1