The de-facto upgrade option for just about any notebook, almost all brands, types and models offer memory upgrade ability. Is it worth it? Depends on what you do with your notebook, if you’re using a notebook for diagnostics or analysis of other computer systems and use some sort of a terminal client do dial into them, your needs are probably met with anything your notebook came supplied with, usually 64Mb.
Fig 2. A 144-pin SO-DIMM and another empty socket as can be found in most notebooks.
If you however run Microsoft Windows applications or an office suite such as Microsoft Office more memory can really help out, especially since a notebook’s harddisk is one of the biggest bottlenecks, more on that later, and you don’t want it to make a huge swap file. 128Mb gets you a long way with most applications, but if you’re the type of user that likes to have lots of windows open and really ‘multitask’ you’re probably better off with 256Mb. Again, more memory really helps with Windows applications due to the average notebook harddisk not exactly being equivalent, in performance, to their desktop brethren.
Notebooks use SO-DIMMs, Small Outline Dual Inline Memory Modules, which are 144-pin memory modules that are roughly one-third the size of a regular 168-pin PC-100 SDRAM module. They feature four or eight memory chips depending on the module’s capacity and can be had up to 256Mb capacity. As with normal SDRAM modules they come in different types, and more importantly qualities. There seems to be a rather large ‘gray’ market for notebook memory modules, as with normal memory modules, that feature brand name memory chips, such as Micron, Samsung, Infineon, etc., but these are mounted on an unnamed PCB, Printed Circuit Board and lack any type number or brand. These are the modules that you’d better stay away from, as there’s no guarantee whether these will work and/or work reliably.
Fig 3. Two 128MB Crucial
144-pin SO-DIMMs installed in the two slots, the original module has been removed.
The modules that are worth your hard earned cash are often referred to as brand-on-brand, which means that the original memory chip manufacturer also designed and manufactured the PCB on which these chips are mounted and sells them as a whole. These modules usually come with a guarantee and are tested and verified prior to leaving the assembly line. They might cost you a few dollars extra but are worth every penny.
Not to sound like we’re plugging Crucial, but they manufacture some of the best notebook memory modules available, and their modules even come with a lifetime guarantee and by using their online database you can be sure the memory will work in your notebook. Furthermore, Crucial’s SO-DIMMs feature Cas-2 timing which is a step up from the Cas-3 timing most other manufacturers use, which basically means you’re getting up to 10% of extra performance due to the reduced memory latency.
More information about Crucial's notebook memory products can be found here: Crucial memory