Memory Size Specifications
	1 MB	2 MB	4 MB	8 MB	16 MB	32 MB	64 MB
30-Pin SIMM, Non-Parity	1x8	2x8	4x8	8x8	16x8	-	-
30-Pin SIMM, Parity	1x9	2x9	4x9	8x9	16x9	-	-
72-Pin SIMM, Non-Parity	256x32	512x32	1x32	2x32	4x32	8x32	16x32
72-Pin SIMM, Parity/ECC	256x36	512x36	1x36	2x36	4x36	8x36	16x36
168-Pin DIMM, Non-Parity	-	-	-	1x64	2x64	4x64	8x64
168-Pin DIMM, Parity/ECC	-	-	-	1x72	2x72	4x72	8x72
D: This is the depth of the module in millions. For each bit of width, there are this many megabits (not bytes) of storage. This number is usually 1, 2, 4 or 8. For smaller SIMMs, it can be 256 or 512; in this case it represent the number of kilobits of depth, instead of megabits. W: This is the width of the module in bits. Each SIMM or DIMM type has the same width. This number is usually 8, 32 or 64 for non-parity modules, or 9, 36 or 72 for parity or ECC modules.     To find the size in megabytes of any module from its "DxW" specification is as follows: take the D and W numbers and multiply them together (if D is 256 or 512, use 0.25 or 0.5 instead). Then, take the product and divide by 8 (for non-parity memory) or 9 (for parity). The result is the size in megabytes.

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Last Update: 9:35 AM 11/18/02