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Yerman

macrumors member
Original poster
Oct 16, 2008
37
3
Hey guys. Just got done reading "Guide to Buying RAM" and the "Understanding Intel Mac RAM" articles at the top of the page (Great stuff by the way). I just got a 3.06 24" iMac. It came with the built in 2 gigs of RAM.

After reading the articles, I decided to check out what OWC had to offer to bring my iMac up to 4 gigs. Well, after discovering that OWC offers several types of RAM, and two of them being labels as "factory original," I decided to open up the iMac and see which RAM came factory in mine.

I discovered I had two 1GB Samsung RAM cards. Cool, I'll go to OWC, and even though the brand doesn't really matter, I'll buy two 2GB Samsung RAM cards and put them in myself. Then I discovered the writing on my RAM cards. They said "1GB PC2-6400s0-666" What the heck...I thought I had 800MHz cards. Is the writing on the card telling me I have 667MHz RAM cards?

Now, to my knowledge I have a "post-april" iMac. If I do an "about this mac" it tells me I have "2GB 800MHz DDR2 SDRAM." This is also confirmed when I select "More Info" from this window and select the "memory" link on the left. So, I don't get it. Does the writing on the Samsung RAM mislead me to believe it is a 667MHz card when in fact they are actually 800MHz, or is the computer somehow thinking that the 667MHz cards are actually 800MHz?

I know what you guys are probably going to say but I thought I would ask. I hope this is not a dumb question. Thanks.
 
Yes you need PC6400 DDR2 memory which is marked 667 on the cards...

Probably for the same reason that the PC5300 memory modules (667MHz) are marked 555..

Anybody know why this should be ??

In the meantime just go ahead and get the PC6400 DDR2 modules for your iMac
 
Yes you need PC6400 DDR2 memory which is marked 667 on the cards...

Probably for the same reason that the PC5300 memory modules (667MHz) are marked 555..

Anybody know why this should be ??

In the meantime just go ahead and get the PC6400 DDR2 modules for your iMac

Thanks logana. So you are saying that for some reason, 800MHz cards say 666 on them instead of 800?
 
Thanks logana. So you are saying that for some reason, 800MHz cards say 666 on them instead of 800?

Yes - PC6400 cards say 666 and are 800MHz. PC5300 cards say 555 and are 667MHz.

So no it is not a dumb question - but the labels on the cards are confusing !!
 
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