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I installed two memory sticks, both of which are 256 MB, but my computer still shows only 256 MB, instead of 512 MB?

Why is it not recognizing the extra RAM?

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migrated from stackoverflow.com Sep 19 '09 at 12:47

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what is the question? –  Mark Sep 19 '09 at 12:43
Please add some details so we can help you. –  middus Sep 19 '09 at 12:44
Just owning two memory sticks doesn't give you more storage. They would both have to be plugged in at the same time. –  Jacob Sep 19 '09 at 12:46
It wasn't really fair to the guys on SU to palm this question off on them. –  pavium Sep 19 '09 at 12:54
What OS is this box running? There's probably some OSs can only address 256 MB of RAM (if you're upgrading to 512MB, it's obviously an old computer). Otherwise, if both are seated properly then one is probably bad –  Nate Koppenhaver Nov 24 '11 at 3:22

2 Answers 2

One is bad? one is not seated properly? Your hardware can only address 256MB of memory? You really bought a 256MB kit consisting of two 128MB sticks? It's a little hard to tell without more information.

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If you are talking about RAM modules, try to plug in only of them instead of both at the same time, to see if either of them is broken or they are in fact just 128M in size. This assumes that your mother board supports running only one RAM module, your mother board manual should tell that. Also make sure that they are properly inserted and oriented the proper way, its easy enough to mess that up when one isn't careful.

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