CHAINTECH 5AGM2, User Manual, Page: 23 / 53

Hardware Setup
17
Because 128MB DIMM is not yet mainstream, the compatibility of 128MB
DIMM can not be 100% guaranteed.
This mainboard supports 3.3v, unbuffered, 4-clock, SDRAM DIMM only.
Buffered, 5V, or 2-clock SDRAM DIMMs should not be used.
This board has DIMM (Dual-in-line Memory Module) sockets to support
SDRAM type DRAM and has the better optimized read timings (7-1-1-1).
The DIMM sockets will quickly replace SIMM as the next module standard
for the PC industry and will become the memory subsystems standardized 64-
bit data interface. Recently, JEDEC committee passed the unbuffered DIMM
pinout specification as a standard for higher speed transfer. The unbuffered
DIMM allows for SDRAM, EDO and FPM DRAM compatibility as well as
pinouts for x64, x72 with parity, x72 with ECC and x80 ECC. The unbuffered
DIMM is distinguished by the keyed notch lying to the right of the centerline
of the DRAM key position as shown in the figure below.