Quick MacBook CD RAM question

[someguy]

I just purchased a 2GB DDR2-800 module for my MacBook, installed it (leaving one of the original 512MB modules installed) and when I turned the machine on, the optical drive made its usual noise, then I got nothing but the sleep light.

I can boot fine with just the 2GB chip installed, and the system runs great, so my question is am I not able to mix memory modules of different bus speeds? Is this just a MacBook thing? I know with DDR the faster modules will reduce their clock speed to match the slower modules, and I thought this was the case with DDR2.

So what gives?

 

[Glennsune]

Sorry to say so, but you cannot mix.

 

[logana]

Is this for the MacBook Core Duo in your signature ?

If so it is because you have hit the maximum ram limit with the 2GB chip (the 2GB + 512MB takes it over...)

see http://guides.macrumors.com/Understanding_Intel_Mac_RAM

I thought that Core Duo machines would not even boot with 2GB Ram chips in the memory slots ?

 

[someguy]

Well, it looks as though I've max'd out the RAM in my MacBook. Might as well sell off the two 512MB chips that came out of it.

Thanks for the info, guys.

 

[alphaod]

You can mix speeds, but it's not recommended at all.