How to read the "Product Name" for RAM modules:
Part #10100, 1 x 36-60 (12),(read as: "one by thirty-six, sixty"), this module is one megabit (1), by (x), thirty-six bits (36), seventy two pin, parity SIMM with an access time of sixty nanoseconds (-60), and twelve chips on the circuit board (12)*. This is a standard four megabyte, Mb, (RAM qty column), parity SIMM.

Parity SIMMs have either 9 or 36 bits, ( x9 or x36). Non-parity SIMMs have 8 or 32 bits, (x8 or x32). Eight and nine bit SIMMs, (x8, x9), have 30 pins. Thirty-two and thirty-six bit SIMMs, (x32, x36), have 72 pins. Sixty-four bit DIMMs, (x64), have 168 pins.

* Note: If the number in parenthesis is accompanied by the "Mb" symbol, the number will be representing the capacity of the module.
Example: Part #15410 DIMM 8x64-60 (64Mb) is a sixty-four megabyte (64Mb) module.

Now, if you know what "type" you require, what part do you need?
Here's how: Find the point on the table where the "type", (x8,x9,x32,x36,x64), intersects with the "size" ,(1Mb,2Mb,etc.), to get the description of the part you need. EDO SIMMs are usually x32.
 

Size	Type
	Non - Parity			Parity
	x8, 30 pin	x32, 72 pin	x64, 168 pin	x9, 30 pin	x36, 72 pin
1Mb	1x8	256x32	-	1x9	256x36
2Mb	2x8	512x32	-	-	512x36
4Mb	4x8	1x32	-	4x9	1x36
8Mb	8x8	2x32	1x64	-	2x36
16Mb	16x8	4x32	2x64	16x9	4x36
32Mb	-	8x32	4x64	-	8x36
64Mb	-	-	8x64	-	-

 

What do the little numbers on the black chip mean?
The numbers identify the type and size of that particular chip. The following is a list of part numbers used by various manufacturers.

MAC VRAM*

*This table is to be used as a general guideline. Increasing resolution beyond 640 x 480 could require more VRAM than listed here.