Yes, I know there's instructions about installing RAM in the Mac user guide. That's not exactly what this is about...
The guide states that RAM must be installed in pairs. Since my iMac has 512 mb of RAM, I'm assuming it has two 256 MB RAM modules installed, correct? Well, if I can only afford another 512 MB of RAM, but not a second one, does that mean I can install one 256 MB RAM module and one 512 MB RAM module (giving me 3/4 a gig of RAM)? Any help/advice would be appreciated.
If your machine supports dual channel memory then its always best (performance wise) to isntall in pairs.
However as the machine tops out at 3GB of ram you would struggle to do that in a pair wouldn't you 
As long as the memory is the same speed I wouldn't worry go with what you can afford.
I am pretty sure its the Mac Pro that requires pairs or kits as they call them.
Just to confirm, can we have your exact machine specs... there are many different types of iMacs.
I a presuming its an intel mac?
But which processor.
As a secondary thought If its the later machines, I am not so sure they do a 256mb Chip??
Thanks. Do you think it'd be safer to go with two of the same RAM modules? Because if I for some reason buy just one and it doesn't seem to work with another of the modules I already have, then I spent money on something I can't use...until I get enough for a second one.
Then again, a "kit" for 1 GB (two 512 MB) would be about $150.00 from the Apple Online store. I should have about enough for that...ugh, it's all very confusing.
Where in the world are you?
I have always advised people who are unsure about memory to go with Crucial.com
Providing you order the correct stuff, if for some reason it doesn't work they will take it back exchange or refund.
Its a little cheaper than apple and is very good quality.
I would just order a 512mb think its about $65 from crucial.
That would give you a gig of memory which would be a nice start.
Where in the world are you?
I'm in Canada, so prices would be a bit more than mentioned on most sites because of currency exchange.
Just to confirm, can we have your exact machine specs... there are many different types of iMacs.I a presuming its an intel mac?
But which processor.
As a secondary thought If its the later machines, I am not so sure they do a 256mb Chip??
Sorry I didn't answer this before. Yes, I have a 1.83 GHz iMac with an intel core 2 duo processor. The exact specifications needed would be...
SO-DIMM (obviously)
667 MHz, PC2-5300, DDR2 667 (DDR2 compliant)
Unbuffered/unregistered
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