Currently there is 4GB of RAM in my August 2012 MBP and 1GB of RAM in my other iMac (2007 or 2008).
I want to max out my MBP to the highest it can go. Could I put the 4GB from the MBP into the iMac to save money and get an upgrade out of both?
The 2007 or 2008 machine will use either 667 MHz or 800 MHz DDR2 RAM. If it is an Early 2009 machine it would use DDR3-1066. Keep in mind that these are Apple introduction dates, not your purchase date. It is entirely possible to have purchased an Early 2008 Mac in 2009 (and doubly so if you purchased from the Refurb store)
The current model Macs use DDR3-1333 RAM, so RAM from it would not be usable in any 2007-2008 DDR2 Mac. We have seen problems using DDR3-1333 RAM in DDR3-1066 Macs as well, so it is a YMMV situation whether you can reuse new RAM modules in an early DDR3 Mac. It depends whether the DDR3-1333 module is correctly programmed to have the SPD (Serial Presence Detect) settings of the 1066 spec as well as the 1333.
We always ask for the Mac identifier number when quoting RAM -- an iMac from 2007/Early 2008 could have 667 MHz or 800 MHz RAM modules.
CanadaRAM supplies RAM memory, drives and upgrades to Mac owners all over Canada http://www.canadaram.com
Hate to spend the money to upgrade both - but I guess this time the family iMac has to come first. We can't even upgrade to Lion yet!
And you may not even want to go the Lion "upgrade' route, and you sure couldn't with just 1GB of RAM "in [your] other iMac (2007 or 2008)".
But 1GB of RAM is really minimal and 4GB RAM and Snow Leopard 10.6.8 makes a nice user experience, (I use a 24" and 4GB myself with that era iMac) or even go with 6 or 8GB if your iMac model supports it.
Check with everymac.com for complete supported specs for your specific model.
Hey it's been a long time since I posted here but I wanted to pass along something.
I was looking to buy my Ram for my late 2011 MBP and was going to buy from OWC or locally but I ended up searching around a came across Patriot Ram that was being sold by Memory Express in Calgary. I figured I would take a chance on buy this Ram because the price was so cheap. I did buy the Ram and did a 5 hour burn in and have been using the Ram for about 3 weeks doing production work with no issues.
Anyway it's a good thing to get great prices so I thought I would share.