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Hello everyone, today we are going to learn about the memory of the laptop

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Memory is also called random access memory, or RAM, or cache

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It can read and write at any time, and it's very fast

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Ii is a temporary data store for an opening system or a running program

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The biggest difference between it and ROM is the volatility of the data

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Data stored in ROM will not be lost when power is turned off,

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but data stored in RAM will disappear when power is turned off

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Laptop memory has evolved from DDR1 in the early days to DDR5,

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which is the first generation of memory to the fifth generation of memory

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Of course there are older memory before the first generation

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I've got a couple of pictures here,

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so let's look at the image of Gen 2 memory first

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It will have the word "PC2" on the memory surface, in this location

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It will have the word "PC3" on it,

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and the low-voltage version will have the word "PC3L" on it

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And then below that is "PC4", "PC5", which is generation 4 and generation 5 memory

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Each generation of memory has a characteristic, is this error prevention interface

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This is generation 2 on the far side, and this is generation 3 a little bit in the middle

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The one in the middle is generation 4, and the one in the exact middle is generation 5

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There is also a type of memory, called onboard memory,

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where the memory particles are all welded on the mainboard

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This memory upgrade is somewhat difficult

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The other one is to put the memory particles on the back of the CPU,

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and the CPU is directly packaged together

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This is Apple's M1 processor,

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and it's a much harder and more demanding memory to replace

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Okay, this is the introduction of the laptop memory