It depends on who's standards your going by, how old the Mac is/what operating system it's running, and what the Mac is used for.
Generally, 2 GB is considered pretty standard and good for everyday use.
Yes, 512MB is 1/4 the size of 2GB.
2000MB
2gb
Upto 2GB expendable memory
2gb
memory saving
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no only a 2gb
2GB
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Not much on anything, but that depends on what you are using.
PC2 5300 is a 240 pin DDR2 memory. This type of memory is commonly found in laptops. It comes in several sizes as well, but the 2GB size is the most common size to purchase this memory.