RAM tech throughout the years

SDRAM synchronous ram (2 notches)

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DDR speed rating x8 = PC speed rating

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DDR-SD RAM (1 notch)

184 PINS

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DDR2 4x faster than normal DDR

200 or 240 PINS

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DDR3 was a little faster

have 240 PINS

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DDR4 current fastest and most common. 

MT/s means MEGA TRANSFER per second

have 288 PINS

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**RAM is based on a SQUARE**

RAM comes double-sided

Or

single sided (blocks only on one side)

The down side to double sided RAM is some motherboards can't take it

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RAM is usually sold in pairs due to CHANNELING

DUAL CHANNEL means they run together

YOU have to put 2 sticks of RAM for PC to function right. 

Otherwise it's Like a POD racer without a engine on one side

Try to use same speed RAM sticks on parallel slots/channels

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RAM PARITY 

NON-ECC has one extra odd number 

ECC has 2 extra

Some motherboards can't take ECC - yet some require it

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SO-DIMM ram sticks

 

are a bit smaller - usually for laptops

LAPTOPs tend to take ram sticks on their side

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SPD chips (serial presence) a tiny square chip hidden on RAM stick. 

It tells you all capacity info on your ram stick in case you lost label. 

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use "CPU-ID CPU-Z" software to read your RAM's SPD info