My system came stock with 1GB RAM. Want to buy 2 2GB cards. Can I just add the new RAM into the slots for a total of 5GB or do I have to remove old and just install the new cards for a total of 4GB?

Any configuring necessary (BIOS, etc.) or is all new RAM PNP?


RAM is Plug-n-Play

If your system is relatively new, it will have DDR2 or DDR3 RAM. DDR2 is usually installed in pairs for performance reasons, and DDR3 is usually installed in 3's, but it's not required.

Crucial.com has a great Memory Advisor Tool which will recommend a type and # of RAM sticks to buy:

Click here for Crucial Memory Advisor tool


You can just install more RAM as long as you have four slots right now (some motherboards only have two, particularly in laptops). Note that you'll want to make sure that you insert the RAM so that it will bank properly. The two 512 sticks (I assume) in there right now should be in the correct places to bank with eachother, so just put the two new sticks in the two other slots (might be next to eachother or might alternate). As long as the RAM are in the correct slots they will dual-channel properly (DDR2 banks in to sets of two, so the sets of two just have to match).

If you only have two slots, then definitely just take out the existing RAM and replace it entirely.

You'll need to make sure you get the right kind of RAM. The RAM needs to be the right generation (DDR, DDR2, DDR3) and as fast as or faster than your current RAM to avoid a loss of performance. It's probably DDR2, look for a speed number that looks like "DDR2 666" or similar. You'll need DDR2 with the same or higher speed number.

No configuration will be necessary, it will work just fine out of the box. You might want to look in BIOS to confirm that the new RAM count is correct, to make sure that it's installed properly faster than the time it takes to boot your OS.


One thing to keep in mind is if you are running a 32 or 64bit OS. If you are running a 32bit operating system, then it will only see 4GB no matter what. Otherwise if you have the empty slots you could run the 5GB, but then it will only run single channel instead of dual or triple. Also keep in mind memory speed and type. If you decide to go for 5GB then there is no point in getting faster memory then what you have. If you go for 4GB you might be able to get faster memory - up to whatever your motherboard supports.

What is better the 4 or 5GB? If the speed of the memory is more important then quantity then go for the 4GB. If quantity is more important then run the 5GB. If your system is DDR3 and supports triple channel, you might want to look at getting 3x 2GB sticks instead.


It depends on how many slots your motherboard has, and if your motherboard supports that configuration. If your manual says that this configuration is supported then you should put the larger modules in the "lower" slots (usually lower-numbered), and the smaller modules in the higher slots.

You should not have to reconfigure anything in the BIOS to take advantage of the new memory, but some operating systems, notably the various variants of Windows, may have specific limitations and you should investigate its details further.


What model system do you have? I would download "System Information for Windows" free here: http://www.gtopala.com/siw-download.html .

Look specifically at the Hardware>System Summary, Hardware>Motherboard and Hardware>Memory. With all that information, and you can post it back here, you will be able to tell everything you want to know.


I'm pretty sure you'll find you have slightly better performance if you remove the 1GB so you end up with a matched pair of RAM. But in reality I doubt it will be that noticeable unless running benchmarking tools, etc.

If you have four slots on the motherboard and two of them are one colour and the other two are another, but the two stick in matching colour slots.

Once you install the RAM (assuming you motherboard does support the type/speed) all it should do is detect a change in the config (more RAM), and prompt you to press a key (F1 or F11, I don't remember off the top of my head) to confirm.

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