Many people think that upgrading there computer memory speeds up there computer system but did you know that the upgrade may be slowing your system down. How can this be possible I added more memory so my system should be faster correct? I say this because as a Computer Technician I have seen many computers with the wrong memory installed. Just because you upgrade your Laptop memory from 1 GB to 2 GB is the memory speed correct? Computer memory or RAM works on the slowest module installed. So for example you have a 512 MB and you have a blank memory module bank and you install a 1 GB module do you truly have 1.5 GB’s of memory? Are they both the same speed? Your PC will show 1.5 GB’s installed however if one module is 3200 and the other 42oo your computer operates at the slower speed ignoring the faster speed. Now have you truly upgraded your memory or are you causing potential damage to your system? Have you installed the proper memory per the manufactures specifications?
The short term for Computer Memory is called RAM.
RAM – Random-access memory is a form of data Storage (Wikipedia). RAM comes in a variety of form factors.
I will only cover the RAM types which work with Laptops and Desktops but will touch on the different types of memory modules briefly.
Searching for RAM can become a bit confusing. The types of RAM seem to be endless.
RAM is searched by specification name and Pin sizes: SIMM, DDR, RDRAM, SODIMM, DIMM, 72-pin, 100-pin, 184-pin Fully Buffered and UN-buffered and finally Speed. What a mouth full. After being confused of the naming and pin size comes the type of RAM speed I will show you how not to make a common mistake on which type of memory is the correct module for your computer system.
Both Desktops and Laptops use DDR, DDR2 or DDR3 RAM DIMM Modules.
DIMM – dual in-line memory module
Laptops – Most laptops today use what is called SO-DIMM memory, (small outline dual in-line memory module). This is a smaller version of the DIMM modules used in most desktop computers.
There are three types of SO-DIMM memory:
SDRAM – which stands for synchronous dynamic random access memory. This type of memory synchronizes itself up with your computer’s processor, allowing smooth access. This type of RAM is used on older Laptops prior to August 2009.
DDR – Stands for Double Data Rate
DDR SDRAM is SDRAM with a double the data rate. This means that it is twice as fast as standard SDRAM, and it is one of the two most common types of memory found in modern laptops manufactured after August 2009.
DDR2 SDRAM is the successor to DDR. Basically, it is capable of running at higher clock speeds. DDR2 and DDR are not compatible as DDR2 is 240 pins and DDR is 186 pins. is yet another upgrade to the original SDRAM concept. The big advantage of this type of memory is that it draws less power than its predecessors, thus creating less power drain on your laptop.
DDR3 SDRAM is double-data-rate three synchronous dynamic random access memory is a random access memory interface technology used for high bandwidth storage. This type of memory is the most costly of the three types.
Below are examples of the three types of Memory and there speeds
DDR
- DDR 100/ PC-1600
- DDR 133 /PC-2100
- DDR 166/ PC-2667
- DDR 200 /PC-3200
DDR2
- DDR2 533 / PC2-4200
- DDR2 400 / PC2-3200
- DDR2 667 / PC2-5300
- DDR2 667 / PC2-5400
DDR3
- DDR3 1066 /PC3-8500
- DDR3 1333 /PC3-10600
- DDR3 1600 /PC3-12800
Now that you have seen the variety of RAM available which is the correct one for your Computer? Always install the proper memory per the manufactures specifications. Many companies like Crucial, Kingston, PNY, Cosiar manufacture memory modules. They often have a memory chart or memory locater to assist you on selecting which memory is the correct RAM specified for your system.
Which Memory is the correct? 

Visit our page at LAPCTEK.com and scroll down and select the Crucial Tech tips Icon. This will open the Crucial Memory Advisor™ – then select the correct memory for your system based on manufacture specifications. Or you can drop use an email at: support@lapcdoctor.com and we will assist you in your memory needs.