Generally, people do not take apart their laptops, with the exception of cleaning the fans occasionally. While a standard RAM (random-access memory) DIMM may seem thin enough to fit in a laptop without requiring any changes, that is not the case. In fact, internal volume is at a high premium in laptops; thus, they use a smaller form factor called SODIMM.
SODIMM stands for Small Outline Dual In-Line Memory Module, and as you may expect from the name, SODIMMs are smaller than DIMMs. According to JEDEC standards, SODIMMs must be 30mm high and 3.8mm thick. Meanwhile, SDR,
DDR (Double Data Rate), DDR2, and DDR3 SODIMMs must be 67.6mm wide. In addition, DDR4 and DDR5 SODIMMs are 69.6mm wide. The last type are PC DIMMs which are 133mm wide.
Similar to the DIMM form factor, there is not a generation of SODIMM form-factored RAM in existence that is compatible. This is due to the fact that form factor is the only major difference between DIMM and SODIMM. Apart from this, there are not any performance impacts beyond increased thermal constraints and physical capacity limits inherent to the smaller form factor.
To differentiate each generation of SODIMM and prevent hardware damage caused by varying voltage requirements between generations, each generation of
SODIMM RAM utilizes a different cut-out “key.” The key position between DDR and DDR2 SODIMM memory is very similar, but other generations of SODIMM RAM have more distinct key locations.
Like desktop DIMMs, SODIMMs have increased the amount of pins they feature. For instance, SDR SODIMMs used to have 144 pins, whereas DDR and DDR2 had 200 pins. Currently, the new and improved DDR3 has a pin count of 204, DDR4 has a pin count of 260, and DDR5 has a pin count of 262. Such increases make it so different generations of SODIMM memory are incompatible with one another.
The small volume of the SODIMM form factor is often found in computers with a limited amount of space. As previously mentioned, this is the reason SODIMMs are primarily found in laptops. Nonetheless, not all laptops use SODIMM memory. Although it may be convenient in terms of being able to upgrade RAM in the future, SODIMM is more complex and expensive than simply soldering RAM chips directly onto the motherboard.
ASAP IT Technology is a leading distributor of SODIMMs by top global manufacturers, such as Compaq, Avant Technology, IBM, HP,
Cisco Memory, and many others. With over 2 billion new, used, obsolete, and hard-to-find items on our database, customers can easily find electromechanical components, electronics, IT hardware, and many other high quality products. Backed by rapid lead times and unmatched cost savings, we carry items for a wide range of industry verticals.
Browse our expansive listings at your leisure, and we invite you to request speedy quotes through our Instant Request for Quote (RFQ) service. We only ask that you include as many of your part requirements as possible including target prices and operational deadlines. Within 15 minutes or less of submission, a dedicated representative will reach out with a competitive quote. For additional questions about our other offered services, call or email us at any time; we are available around the clock!
