06-06-2009, 10:57 AM

Hi,

There's been some discussion on the Net about this, so I thought I'd just put my experiences down for posterity and hopefully some day someone Googles this and is able to benefit from it.

I own a second-generation MacBook. Intel Core2 Duo, 1.83 GHz. White plastic, 13 inch screen. When it came out it had 512 MB RAM as standard, upgradeable to either 1 or 2 Gigs.

Apple officially states that it cannot handle more than 2 Gigs, however there are reports on the Net that it can handle about 3 Gigs.

I just put in 2 x 2 Gig RAM modules (200 pin SODIMM, 667 MHz PC-5300). I can confirm that my MacBook recognizes that it has 4 Gigs installed, and can address about 3 Gigs of it. It's a hardware limitation that causes it to only be able to address 3 Gigs; I'm dual booting with Ubuntu, which is similarly limited to using about 3 Gigs of it.

The video circuits are sharing some of the RAM. At least 64 MB. So the total amount being used is a little over 3 Gigs.

If you use an identical pair of memory modules, you get a performance boost that someone on the Net claims to have measured at 6-8%. Some other people on the Net claim to have tried faster RAM (PC-6400, 800 MHz) and say that they've had random stability issues, so don't put in faster RAM than you need. You don't benefit from it in any way. You can use mismatched memory (such as a 1 Gig module and a 2 Gig module), but you take a performance hit.

As is always the case, when my laptop was on the market, 2 Gigs was prohibitively expensive and 4 Gigs was just being silly, but now the market's moved on, and software has bloated to fill those Gigs. It was a relatively small amount of cash at the computer shop this afternoon for me to max it out and get some more life out of my puter. The CPU is still competitive, so as long as I'm not taxing the video hardware, my puter is still useful.

So, like I said, just for the record, the 2nd generation MacBook can handle 3 Gigs. Right now I have Dashboard, Firefox, BOINC, a virus scanner, Terminal, and Activity Monitor running and I have had exactly 0 page outs since booting! When I had 1 Gig installed it would always have at least some minor paging activity.

Richard

06-06-2009, 12:40 PM

Thanks for the informative post Richard. We've seen several posts recently about putting 3 GB in a machine which is only designed (according to Apple) for 2 GB.

Regards.

07-10-2009, 12:57 PM

why do need a virus scanner, you have a mac , i kid you.

07-10-2009, 02:29 PM

I had three gigs in my old second generation whitebook, in the form of 1 one gig and one two gig chips. Did it that way because then I could upgrade both my and my wife's blackbook of the same vintage to three even though I bought a pair of two gig modules.

I've since upgraded to a 13" macbook pro which "only" has two gig. I do notice some slow downs that I didn't get on my old machine when I have lots of safari windows, photoshop, and my VM going even though this machine is technically faster so it does make a difference. I'll be upgrading this one to four gigs because even though it can take eight, it costs more than the machine cost to do this at the moment.

07-10-2009, 02:38 PM

Dual channel memory offers only a minuscule performance boost in most real world applications. There are only two places where you would see the benefit, benchmarks and memory intensive programs. It is not noticeable in daily use of the average user. Hence it's better to save money and get 3GB instead of 4GB.