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BazC
09-07-2006, 12:44 AM
I'm seriously considering one of the new iMacs but I have some queries about RAM. The new machines will take up to 3 gigs of RAM. Ideally I would buy 1 gig from Apple and add another later but of course Apple will only supply 1 gig as 2 512MB sticks (Grrr!) and they still only appear to have 2 slots so ultimately I'd have to dump the (expensive) Apple RAM to add 2 1gig sticks. Some people insist Apple RAM is the best so maybe it's worth paying the premium and buying 2 gigs straight away? Is good quality RAM from another manufacturer as good? After all Apple don't actually make the RAM do they?

Secondly, they used to say with the G5s that RAM should only be added in matched pairs. Does that not matter any more? Apple supply 3 gigs of RAM in the new iMacs as a 1gig stick and a 2gig stick. If it doesn't matter any more I could maybe order the machine with 1 gig and replace 1 512mb stick with a 1gig later and replace the other later still.

All thoughts and suggestions gratefully received!:D - Baz

Captain Obvious
09-07-2006, 01:17 AM
Is good quality RAM from another manufacturer as good?
Yes, it is.


After all Apple don't actually make the RAM do they?
No, they don't.


Secondly, they used to say with the G5s that RAM should only be added in matched pairs. Does that not matter any more?
In any machine that uses the RAM for video memory, like the lowest-end iMac, Mac mini or Macbook, matching them up will provide a good performance increase. In the other machines, I see no reason to care. 3 gigabytes of single channel will be better than 2 gigabytes of dual channel.

BazC
09-07-2006, 02:03 AM
Thanks for the info Cap'n! I don't understand this though..


3 gigabytes of single channel will be better than 2 gigabytes of dual channel.

By channel do you mean RAM slot or processor or what? Excuse my ignorance! :D

Captain Obvious
09-07-2006, 02:07 AM
Matched pairs of RAM = dual channel.

Unmatched = single channel.

You're welcome. :p

BazC
09-07-2006, 02:12 AM
Ah, gotcha! Thanks mate!

jeremyhardin
09-07-2006, 09:42 AM
very useful info, thanks!

Darttman
09-07-2006, 10:01 AM
Look at the timing (CasLatency)that apple is using. Find the CAS, RAS and latency specs and the manufacturer. This should help in picking out memory to comply with the mobo.

Hope this helps

BazC
09-07-2006, 10:10 AM
Look at the timing (CasLatency)that apple is using. Find the CAS, RAS and latency specs and the manufacturer. This should help in picking out memory to comply with the mobo.

Hope this helps

Thanks for the info Darttman!

avkills
09-07-2006, 11:13 AM
Just make sure you buy something that matches whatever it says in the manual. I've bought RAM at Microcenter for my G5 and have had no problems. My latest was a pair of 1GB sticks made by Kingston.

-mark

mike_stening
09-07-2006, 11:20 AM
just to back that up we only use kingston ram in all our macs in our agency, from the imacs through to our mac pro G5's, though we do tend to buy in pairs. and we have had no problems so far with bad ram, the only thing we had fail was one G5 lost a processor for no real reason but that is it.

Captain Obvious
09-07-2006, 11:24 AM
Macs are not as finnicky about memory as people seem to think. As long as the memory isn't faulty (or downright poor quality), it'll work just fine.

BazC
09-07-2006, 11:38 AM
Good to know, thanks folks! BTW I've always used Kingston RAM too and never had any problems.


Any suggestions where to buy RAM in the UK? I just checked the prices for PC2-5300 at Micro Anvica and they were as expensive as Apple! :eek:

Captain Obvious
09-07-2006, 01:59 PM
I bought two 2 gigabyte sticks of 800MHz DDR2 for my new computer for like 30% more than the 2 gigabyte upgrade costs in the iMac...

BazC
09-07-2006, 02:20 PM
Wow, I bet it wasn't in England though! :(

gerry_g
09-07-2006, 04:03 PM
Last time I bought memory for a G5 was from W Store in the UK an had to fork out this much, never given me any trouble though

2x 1GB (2GB) Kingston Memory - DDR SDRAM - 400 MHz / PC3200
£*272.56

gerry_g
09-07-2006, 04:05 PM
Most G4's still use sodium dims and are far more expensive though, sorry 'bout that

Darttman
09-12-2006, 08:23 AM
A decent article about upgrades for the new macs http://www.anandtech.com/mac/showdoc.aspx?i=2832

I was wondering how apple was handling large amounts of memory with no ECC requirements and now I know thanks to this article. Appears they use and AMB advanced memory buffer to handle just this problem. As you know if you stuff 2+ gigs of ram in a box you start to experience memory errors so this is why most manufactures require ECC type memory.
Turns out apple corrects this with a controller AMB but this introduces some latency. It will be interesting to see what the article finds in further memory study down the road.

I recommend this article if you’re looking into upgrading some memory for the sexy new macs.:thumbsup: