PC*Base #7 – RAM

Sorry for the delay, but Hurricane Sandy left me without proper internet access for a week. This week we are taking a look at RAM (Random Access Memory). RAM is basically the short-term memory function for your PC. When your PC starts thinking about something, or runs an application, it puts it all in RAM so it can access it faster than it would if it kept all of that information on the hard drive. The more RAM you have, the more apps your PC can run concurrently.

For the most part picking RAM is simple. The hard part is knowing some of the terminology involved. RAM is sold in pairs called DIMM’s (Dual In-Line Memory Module). They can be sold individually, but that is extremely rare for a desktop computer today. Laptop Memory is often sold as an individual SIMM (Single In-Line Memory Module).

The biggest factors for choosing RAM are size and price. There are other differences I will discuss, but those are the big ones. If you are building a new PC, you are going to need DDR3 SDRAM (Double Data Rate Type 3, Synchronous Dynamic Random Access Memory). Aside from Laptop memory which is much smaller, DDR3 SDRAM is pretty much the only thing being sold so it keeps it simple.

The first minor difference is the clock speed of the RAM. The speed will make your RAM cost more, but faster RAM doesn’t often give a real world performance difference. Today the standard speeds I see most often are 1333 MHZ, and 1600 MHz. I prefer 1600 MHz because the price difference between the two are slight. They sell RAM all the way up to 2800 MHz, but unless your time literally = money, this isn’t necessary in the grand scheme of things. If you are building a PC and it’s not your money, feel free and get the fastest thing possible, but don’t be surprised if you don’t see a difference.

The other minor difference is the transfer speed which usually goes hand in hand with the clock speed. Transfer speed is just what it sounds like. It’s the maximum speed the RAM will transfer data at. RAM with a clock speed of 1333 MHz will usually have a transfer speed of 10666 MB/s, while 1600 MHz RAM will usually have a transfer speed of 12800 MB/s. If you ever see RAM listed as 1600 MHz, but 10666 MB/s then you should probably avoid it.

The most important differentiator between different types of RAM is the size. Size of RAM should be listed in gigabytes incrementing in even amounts from 2 to 32. These days the standard in new computers should be 8 GB of RAM, which can be found for as low as $30. You can probably get away with only 4 GB if you want to be cheap, but if you are building a PC that you want to last in the future, spending the extra few dollars is probably a good idea. Some people buy 16 GB, but I can’t see needing that much memory any time soon.

One important thing to note, is that you need to run a 64 bit operating system for your computer to take advantage of anything over 4 GB of RAM. Windows XP is only a 32 Bit operating system. There are 64 Bit versions of Windows 7, and Windows 8, but you need to make sure you install the correct version or you will be wasting memory with anything over 4 GB.

Looking at memory for sale can be a bit confusing. Let’s take a look at an ad from Newegg and break down what you’re seeing. G. SKILL is the manufacturer, and Ripjaws Series is one of G. Skills brands. Often a manufacturer will have multiple brands under their name to differentiate between their low-end and high-end types. 8GB (2 x 4GB) means that the total is 8GB and you are getting 2 DIMM’s that are 4GB a piece. 240-Pin DDR3 SDRAM is telling you that it’s DDR3. DDR3 1600 (PC3 12800) is telling you that it is DDR3 at 1600 MHz with a transfer speed of 12800 MB/s. The rest in the first part of the ad is the model number.

It also lists a timing of 9-9-9-24-2N. Explaining this is outside of the scope of the article, and mostly unnecessary to know. When you plug the RAM into your motherboard and boot your machine up, the motherboard will automatically detect the timing and correctly set it. I’ll simplify Cas Latency and say it’s how fast the RAM will talk to itself. A lower number is better, but in general you should see the number vary from 8 to 11. Just like the clock speed, this isn’t really important unless a few seconds lost throughout your day is costing you money.

Now that we have the CPU, and RAM connected up to the motherboard, in the video above, you can test out the parts previously covered (case, power supply, motherboard, CPU, and RAM). The video at the bottom of the article will illustrate how to put all of those items together and test out your computer without a hard drive.

Next week we’ll take a look at Computer Monitors. If you are reading this you probably already have one, but maybe you’ve been eyeing a bigger, badder monitor. I’ll show you what to look for, and what to look out for when buying a nice replacement.

So, what do you think?