Adding or Replacing Memory (what you need to know)

Dec 28, 2010
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(EDIT: I am new to this forum and I really like to give back before I get an answer to things I ask about. Today I chose to take my time to do so in the form of a computer memory buyers guide to basic information. Although this may seem like a lot to consume for the purchase of a stick of memory you will appreciate it when your work is not lost, your computer is not damaged, and your money stays in your pocket.
Please forgive my typos, sticking keys, and style, I did not have much time to write this and proof it.)

Potential memory buyer. Here you will find the information you may not have realized you needed to know before making your memory purchase.

Please take this advice to heart, ask others about it, and know that in the end you will save time, money, and frustration from problems.

You can buy a single stick of RAM for your PC, retailers only want your money and are very good at extracting it from your pocket. When you leave the store you are on your own. If you add just one stick of memory then your RAM will be unmatched, if using more than a single stick even if it is the same brand and model number. Potentially this will create issues you want to aviod. Please read this in its entirety.

Ram comes in various brands, voltages, and timings. You want to be sure you match those specification if you desire to keep the same type of memory you have. It is possible to run a PC with unmatched brands and RAM specifications. If you are technically well suited to manually setting all of the timings and voltages outside the RAM makers specifications, and running stability test on your PC to insure those settings will work without producing errors. You may get away with this practice. But what about the unmatched brand? Please do all you can to avoid adding memory without getting the brand and everything else to match up with what you have. This is not the perfect solution but will work, just not to the very best performance that you will find in matched memory

Did I scare you just a little bit? If I did that is a very good thing.

Many people do buy RAM and just put it in the computer and go on their way, sometimes it works and many times it does not. During the times it does work those same people often have errors they blame on various things in their PC. They do not realize what caused the errors. They could have a system hang up requiring a re-boot, they might lose data which never saved to a file, Etc and so on. Chances are they will never say my memory cause that to happen, nor will many service technicians when you go in for a repair. Instead you end up replacing hard disk drives, motherboards, power supplies, and everything but the cause of the problem.

Go to a computer store where they have staff that can help you select RAM that will match the brand, timing, and voltage of the RAM you presently have installed. Most on line dealers will not do this, they simply have a list of RAM that will run based on a chart of computer manufacturers and models. Even many big stores work this way, you really need technical and experienced help who knows about memory. TAKE THIS GUIDE WITH YOU TO REFERENCE. Do not get in a situation that is NOT GOOD ENOUGH. Give it to the technician and tell him to look it over briefly that these are your concerns. At the least he will know you are serious about getting the right memory.

Computers, nearly every single one of them, will run RAM of various brands, voltages and timings. The problem is that memory is not a plug and play component like many computer components are today. Although you can just put new RAM in and turn the computer on, the computer will usually start up. Where the problem comes in is when the RAM goes under stress, meaning being used by programs. The more stress or usage the RAM receives the more the likelihood it will produce errors if brand, timings or voltages are not correct. Restateing, this can occur with a non matching brand of memory due to how the memory was made. These problems can be very difficult isolate when you have to determine the cause. You also have to find a compromise setting for RAM with different specifications to eliminate these problems. You will need to know a lot about how to manually set RAM timings and voltages so you do not BURN UP YOUR RAM, potentially damage your computer, loose important data, or have programs or the computer suddenly stop running. If you run into a problem because the brand of the RAM is different the only way to FIX it may be to obtain the same brand (buy more memory to replace some of what you just purchased).

This is actually very simple. Be sure you are at a store that has specialized help in the form of a certified technician who knows about memory (not all PC techs do). Explain to the technician you want your RAM type, settings and brand to match what you presently have and be sure the new RAM will work with your computer if you completely change to something different. There have been times when matching settings will not work so be sure you have a return period without to many restrictions. RAM is an imperfect thing and just like an automobile you can get a bad product. The best bet is to ask them to install the RAM and and do a simple test for you. It is much better to have a complete test done but this takes time. You can also ask them to give you a place where you can locate and download a memory testing program (see highlighted text below) you can run at home for a longer period. I test my memory for a minimum of 8 hours per stick and then 6 hours times the number of total stick I have installed with all sticks combined. (ie:: 4 sticks = 4x6hours = 24 hours of testing with all sticks combined) This takes a while but when I am done I am pretty certain if I see an error later it will not be memory related. These test can be hard for a non technical type to use, be prepared to call a friend who knows about htings like this. A lot of people do these days so they should not be to hard to locate.

Personally I build a lot of computers for gaming purposes as a hobby, the computers are set to run at voltages beyond the manufacturers specifications in many areas. If you are running a high end graphics PC or other high end PC you may want to replace all of your RAM even if you have the same exact brand and model of RAM to add to your computer. The reason for this is because RAM manufacturers have a process by which they test much of the product they produce to match it to other memory of like kind. This testing is very intricate and goes beyond matching settings and voltage. It results in something call a MEMORY KIT. Memory kits come in various configurations, for example you can find a kit of 2 sticks of memory, 3 sticks, and more where each stick may have 512 MB, 1 GB, 2 GB, 4 GB, etc of capacity. Each kit has the exact brand, settings and voltage plus other things consumers have no control over when the sticks were made. Most importantly each of the sticks of memory has been tested against each other stick in the kit to insure they run at the same speed and have the same operating characteristics as the other sticks in the kit. Hence they are called a MATCHED MEMORY KIT.

The speed of memory you put in your PC is important because putting a slower speed stick of memory in your PC will cause all of your memory to run at that slower speed. It can also cause the computer not to run. Having memory that is faster than your PC is designed to run may be perfectly fine as long as it is the same brand, timings, voltage, and it is designed to run in the configuration you desire. Get memory that is to fast and it may not be able to run slowly enough for your computer to use it. Personally I like to buy faster memory because it gives me some head room to speed it up later if desired and in general the memory is of a better manufacturing quality the faster it is. Still this is something you need technical advice on at the time of purchase so when asking for a PC tech to help you ask for one who knows much about memory. Usually they will be technicians who overclock computers for a hobby or on the job.

In almost every situation I advise people to locate and run a matched kit of memory in their computer. If it is a high end PC they should replace all the memory they have with matched memory so everything functions the exactly the same way. This way they also avoid brand conflicts and most important they are getting memory matched for things consumers can not match in the store or elsewhere. Things only the manufacturer can match with highly specialized equipment. See if the technician will put the memory in for you and give you advice on locating and running a memory test program at home. One of the best memory test programs is free, it is called memtest+ and can be found at where you can download it. This test program requires you to create an ISO disk or USB fob. Creating the ISO disk will require additional software available free online. The USB fob or ISO disk will run before windows gets a chance to start and will remain running until you stop it. Windows will never start during the testing so be prepared to leave your computer alone to finish the test.

If the computer is slower, not used for anything really important, and the user does not have the funds to buy a kit (kits are generally not that much money depending on the type of memory) I would tell them to at least make sure the memory specifications are the same and preferably get the same brand name they already have. You have a fair chance to get something which will work if brand, timings and voltages match. What you really want is the same brand and exact model of memory you already have installed. Be cautious of a savy sales guy trying to get you to switch by telling you it will be fine. The fact is once you leave the problem is your not theirs and the worst that could happen to them is you might return the product.

WITH MEMORY THE BRAND IS VERY IMPORTANT IF YOUR ARE ADDING MORE MEMORY TO A PC AND NOT REPLACING YOUR PRESENT MEMORY WITH ALL NEW MEMORY. Compare this to the three little pigs homes, straw, sticks, and bricks. Respectively each is better than the other because they are made differently. (never thought that would come in handy LOL)

Enjoy your shopping, find a good well stocked store, a return policy that is useful, a technician that knows about memory, and take this write up with you when you shop. Give a copy to the technician and tell him a guy on the internet scared you a little and you want to be safe. Some may say this is not that important but if they do don't let your guard down.

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