upgrading ram on imac to 8gb question

[kaufman]

Hello

Well in the end i finally ordered an i7 imac refurb, i wanted a mac pro but just could not afford it in the end and weighing things up it seems the right decision for me.

I wanted to ask a question about upgrading the ram.

Is it still best to install in pairs?

I have the choice of putting 1 x 4gb stick in or 2 x 2gb sticks in to make it to 8gb ram.

I'd rather buy the 4gb as it would save me money in the long run but remembered something about installing in pairs made the computer work better.

 

[Hellhammer]

Installing them in pairs enables dual-channeling but that's not that important as most apps don't need that high memory bandwidth. I would get the 4GB module but there was some issues with single 4GB module, it had to be in certain slot to work properly but that's not hard to figure out

 

[kaufman]

Installing them in pairs enables dual-channeling but that's not that important as most apps don't need that high memory bandwidth. I would get the 4GB module but there was some issues with single 4GB module, it had to be in certain slot to work properly but that's not hard to figure out

thanks, i want to run logic 9 in 64 bit if i can to access the extra ram, so buying the 4gb single module will improve performance ?

 

[Hellhammer]

thanks, i want to run logic 9 in 64 bit if i can to access the extra ram, so buying the 4gb single module will improve performance ?

Of course it will because it's 4GB more RAM, i.e. twice as much as you had before.

 

[kaufman]

Of course it will because it's 4GB more RAM, i.e. twice as much as you had before.

sure yes i was only asking in terms of 64 bit as i know in 32bit it will only recognise 4gb ram.

Looking at the apple site it appears best to take the 2 x 2GB modules out of the top slots and put them in the bottom slots then put the single 4GB in the top slot.

"i5 and i7 Quad Core iMac computers come with both top memory slots populated. These computers will not start up if only a single DIMM is installed in any bottom slot; these computers should operate normally with a single DIMM installed in any top slot. Core Duo iMac computers should operate normally with a single DIMM installed in any slot, top or bottom. ("Top" and "bottom" slots refer to the orientation of the slots in the pictures below. "Top" refers to the slots closest to the display; "bottom" refers to the slots closest to the stand)."

 

[mlblacy]

search around a bit...

someone just posted a link to some benchmarking tests. My recollection is that the 12gb configs seem to actually run a tad slower than the 8's. It did not quite sum up as a case of mismatched pairs, but that was the implication. I was going to order my i7 with the 2-4gb's for the 12gb, but am probably just going to stick with the 8gb initially. The 16gb's seem still a little high on price for now, and I am sure the 4gb chips will come down in a bit.

For what it is worth the Apple tech told me ram did not be installed in pairs...

cheers,
michael

PS: I can't seem to find the link, but I will look some more... if anyone has some good advice chime in. The price difference between the two 8gb configs isn't a big deal, and my personal pref would be to have 12gb over 8gb,