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macmesser

macrumors 6502a
Original poster
Aug 13, 2012
921
198
Long Island, NY USA
I'm upgrading RAM to 6GB (max for this model). After installing OWC module I'm seeing the 6GB, but RAM speed is shown at 533MHz. Is this nominal RAM speed for this model? I thought it was higher so I'm wondering if I might have inadvertently switched modules as I was also upgrading a 2008 2.4 GHz MacBook. The 08 MacBook Pro shows RAM speed at 667 MHz, which I think is correct. Anyone know where I can get the actual spec values? Thanks for any insights.
 
That model Macbook uses PC2-5300 that runs at 667Mhz. You may have or have purchased PC2-4200 memory. PC2-4200 runs at 533Mhz and will work in your machine. If possible, check the memory sticks themselves to make sure that it is labeled as being PC2-5300 or return it.
 
That model Macbook uses PC2-5300 that runs at 667Mhz. You may have or have purchased PC2-4200 memory. PC2-4200 runs at 533Mhz and will work in your machine. If possible, check the memory sticks themselves to make sure that it is labeled as being PC2-5300 or return it.

Thanks for reply. Yep, that seems to be what I did. There is no label on the module indicating PC or PC2 but OWC refers to the module as PC5300. I don't know if they have PC2 since this is what they recommended. Will check with them. 6GB RAM at 533 MHz vs. at 667 MHz might be noticeable on an old machine but wouldn't be that big of a difference.
 
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That model Macbook uses PC2-5300 that runs at 667Mhz. You may have or have purchased PC2-4200 memory. PC2-4200 runs at 533Mhz and will work in your machine. If possible, check the memory sticks themselves to make sure that it is labeled as being PC2-5300 or return it.

By mistake, I actually tried a 4GB PC6400 module with what I thought was an existing PC5300 module, and it ran at 533MHz. The 2GB module must have been PC2-4200, although it was labeled 5300. When the PC5300 module was removed and only the PC6400 remained, it ran at 800MHz (according to system report). Is it OK to use the PC6400 at 800MHz in this machine? If so I could add a 2GB PC6400 module for the max 6GB for this model, running at 800MHz. That's around a 20% RAM speed boost for the price of a 2GB PC6400 module ($30 at OWC) so if it's not harmful I would do it.

OK to use 800MHz RAM instead of 667MHz in this model, or would this be not advisable?

Does the fact that the RAM speed is 533MHz with the 4GB PC6400 module plus a 2GB module indicate that the 2GB module must have been a PC2-4200?
 
Just here to say 800MHz RAM works perfectly fine in that model. The chipset supports it fully. Apple even shipped it in the Mid 2009 ones that were just a very slight spec bump before the polycarbonate unibody ones came out.

I pulled 2x2GB 800MHz chips from a dead HP with a GPU failure and stuck them in an Early 2009 MacBook I got off eBay. Coupled with a cheap 120GB SSD and it's a budget screamer!

As for the Early 2008 MacBook Pro, it is 667MHz and they can be picky about using 800MHz alone.
 
You can certainly use faster memory in that machine.

Thanks. Going for it.

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Just here to say 800MHz RAM works perfectly fine in that model. The chipset supports it fully. Apple even shipped it in the Mid 2009 ones that were just a very slight spec bump before the polycarbonate unibody ones came out.

I pulled 2x2GB 800MHz chips from a dead HP with a GPU failure and stuck them in an Early 2009 MacBook I got off eBay. Coupled with a cheap 120GB SSD and it's a budget screamer!

As for the Early 2008 MacBook Pro, it is 667MHz and they can be picky about using 800MHz alone.

Thanks for sharing. Now that I know everything is compatible I'll be doing the same thing to mine.
 
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