Difference between single and 2 sided memory

[fixthat]

My search of the question brings up ancient replies referring to single or dual bank addressing irregardless of number of chips, but I have a collection of 1 GB ddr2 5300 with a small handful of ram with chips on one side. Are these better or worse, is there a preferred purpose for these?

 

[bigpinkdragon286]

Single sided RAM is single rank. Double sided RAM is usually dual rank. There is also quad and octal rank memory.

The purpose of multi-rank modules is to increase module density. Another benefit of multiple rank is, having more open memory pages, which in some cases can increase performance.

A downside to all of this however is that more ranks increase loading on the memory controller, and each controller has a limit to how many ranks it can handle, and how fast it can handle them.

A perfect example is the new Ryzen CPU. The memory controller appears to give better performance with dual rank than single rank, for a given memory speed, but folks are finding that you can't clock the dual rank modules as high. The memory controller just doesn't tolerate it as easily.

As far as the memory you have is concerned, it's not really better or worse when you aren't comparing it to anything. Dual rank modules might give you a very small performance advantage from time to time, but the single rank modules should be compatible with more memory controllers.