How to Find a RAM Kit
Upgrading your computer memory is a great way to increase your system's overall performance, but there are a few things you do need to be aware of before you start. The first thing to look for is always to make sure the RAM will work in your system.
How Do Memory Modules Differ?
One of the most important considerations when looking for RAM is ensuring that you find the right RAM for your computer. This is particularly important when comparing DDR3 and DDR2 because the packages they come in are so very similar. Both DDR3 and DDR2 use 240-pin DIMM packages, but the two memory standards are physically and electrically incompatible. While these are not the only memory types to use the same basic package, they are the only two to use the same pin count. A standard DIMM is 133.35 millimeters long and 30 millimeters high, regardless of type. Luckily there are ways to tell the two types apart:
- DDR2: Unbuffered modules run at 1.8 Volts and feature a voltage notch 70.68 millimeters from the left edge of the package.
- DDR3: Unbuffered modules run at 1.5 Volts and feature a voltage notch 54.68 millimeters from the left edge of the package.
What About Laptops?
Laptops have altogether different requirements from desktop computers, based on their overall smaller size and greater portability. Most worry less about overall performance and more about physical size and power consumption as things like battery life are more important than eking the absolute maximum data rate out of DDR3 SDRAM. There are a few things to look out for when installing Samsung RAM in a laptop motherboard:
- SODIMM: A DDR3 SODIMM is still 30 millimeters high, but only 67.6 millimeters long with a voltage notch 24.8 millimeters from the left edge. It has 204 pins instead of 240.
- Error-Checking: Because laptop memory is not used in servers, SODIMMs only support non-ECC RAM. This lets them get away with fewer pins while still using the same data protocols.
How RAM Kits Work
Many computers use dual channel memory installations, and that means that if you want 8 GB DDR3, you are better off with two Samsung 4 GB DDR3 PC3-10600 DIMMs than with a single 8 GB PC3 module. The advantage of dual channel mode is that it effectively doubles the bandwidth by enabling the processor to draw from two modules at the same time. The memory controller has to be set up to handle it, and it does not always increase the total capacity of the system, but it does provide a big increase in memory limited situations.