What is SDRAM?

[Xanthic]

Hey guys, I've been looking around at Mobo / Cpu / RAM for an upgrade, and I keep seeing DDR4 SDRAM, so, what is SDRAM compared to DRAM?

 

[Paul NZ]

ram

 

[Shaun o]

SD ram is short for,

Single Density Random Access Memory
Data can only be accessed in one pass of the memory or clock cycle of it.

DDR ram is short for,

Dual Data Random Access memory.
Where in a single memory pass, or clock cycle two bits of data can be read from the memory Be it on a read or a write cycle of the memory.

This effectively increases the amount of data you can process in a shorter amount of time since your executing two commands per memory clock cycle.

 

[k1114]

It's all the same just being more specific. All desktop ram is ram, dram, sdram. It's like saying car, rwd car, fr (front engine, rwd) car.

Synchronous dynamic not single density, that doesn't even make sense as they are always going to be the same density on a single stick.

 

[Xanthic]

It's all the same just being more specific. All desktop ram is ram, dram, sdram. It's like saying car, rwd car, fr (front engine, rwd) car.

Synchronous dynamic not single density, that doesn't even make sense as they are always going to be the same density on a single stick.

Would it be okay spending like $10 less for SDRAM?

 

[Phillip Corcoran]

Shaun o said:

"SDRAM is short for Single Density Random Access Memory"

That's not correct.

SDRAM = Synchronous Dynamic Random Access Memory

https://techterms.com/definition/sdram

 

[k1114]

Where are you finding ddr4 ram for $10? How much ram?

 

[k1114]

SD ram is short for,

Single Density Random Access Memory
Data can only be accessed in one pass of the memory or clock cycle of it.

DDR ram is short for,

Dual Data Random Access memory.
Where in a single memory pass, or clock cycle two bits of data can be read from the memory Be it on a read or a write cycle of the memory.

This effectively increases the amount of data you can process in a shorter amount of time since your executing two commands per memory clock cycle.

How would the density of ram have anything to do with having one transfer per cycle? I can understand mixing sdr sdram vs ddr sdram but that's not the case. Single data rate, sdr is not used on pcs, at least not since the 90s before ddr came around, back when 16MB of ram was top of the line. Ddr4 was mentioned so it's definitely not about sdr.

The opposite of sdram, synchronous dynamic would be asram, asynchronous static which isn't used either as ssram, synchronous static is faster.