How much RAM for iMac?

aware

macrumors member
Original poster
Nov 23, 2012
67
1
Hi, i'm looking for iMac 21 2013. I use Chrome and Xcode mostly. Is 8GB ram enough or do i need 16GB ram if i currently have 4GB of page outs and 680MB of swap used in my MBP with 8GB ram? How much ram will you choose?
 
Last edited:

keigo

macrumors regular
Nov 6, 2006
245
6
Hi, i'm looking for iMac 21 2013. I use Chrome and Xcode mostly. Is 8GB ram enough or do i need 16GB ram if i currently have 4GB of page outs and 680MB of swap used in my MBP with 8GB ram? How much ram will you choose?
I currently have 24gb ram on my 27" iMac late 2013 and I'm still facing page out..

look like 32gb ram is the way for me.
 

\-V-/

Suspended
May 3, 2012
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How much Ram for iMac?

I'd go with 16 GB... especially if your photo library is gigantic. 8 GB would get you by just fine, but RAM is cheap.
 

yjchua95

macrumors 604
Apr 23, 2011
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GVA, KUL, MEL (current), ZQN
Hi, i'm looking for iMac 21 2013. I use Chrome and Xcode mostly. Is 8GB ram enough or do i need 16GB ram if i currently have 4GB of page outs and 680MB of swap used in my MBP with 8GB ram? How much ram will you choose?
You can't upgrade RAM in the 21.5" after purchase (actually it's possible, but it's almost impossible to open it up).

Go for 16GB.
 

\-V-/

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May 3, 2012
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How much Ram for iMac?

How do you replace the hard drive in iMac?
By bringing it to Apple or an Apple-certified tech. It's a pain in the butt and isn't worth doing it yourself. It requires using suction cups to remove the front panel glass, among other things. iMacs have never been particularly fun for this task. On top of all this, if it's a newer Mac, if you try using a third-party hard drive it will cause the hardware test to fail: http://tuaw.com/2011/05/12/owc-replacing-main-hard-drive-with-third-party-is-not-an-option/

There are ways around it, but they're also a pain. Apple is going to great lengths so you won't fiddle with the insides.
 

MartinAppleGuy

macrumors 68020
Sep 27, 2013
2,243
888
I have opened all of my apps on my iMac (8Gb of RAM) and it was only using 50% of RAM resources. Plus, RAM pressure has never went past green.
 

firedept

macrumors 603
Jul 8, 2011
5,607
454
Somewhere!
Go for 16GB. Not worth regretting down the road that you wish you had done it in the first place. On the 21" iMac it is darn near impossible to do it later.

As for HDD replacement, I wouldn't be surprised if Apple just replaced the iMac if it was under warranty rather than replace the drive. Especially for the new iMac's.
 

joe-h2o

macrumors 65816
Jun 24, 2012
1,004
443
By bringing it to Apple or an Apple-certified tech. It's a pain in the butt and isn't worth doing it yourself. It requires using suction cups to remove the front panel glass, among other things. iMacs have never been particularly fun for this task. On top of all this, if it's a newer Mac, if you try using a third-party hard drive it will cause the hardware test to fail: http://tuaw.com/2011/05/12/owc-replacing-main-hard-drive-with-third-party-is-not-an-option/

There are ways around it, but they're also a pain. Apple is going to great lengths so you won't fiddle with the insides.
This is extremely out of date information. You do not need suction cups any more, you just need a guitar pick (cheap) or the official cutting tool ($10) to cut the tape holding the display on. This takes about 10 minutes. Replacing the screen requires fresh double sided tape that can be bought from anywhere (cheap) or from ebay/another supplier for the official Apple pieces (a few dollars).

The internal layout is simple and elegant and uses standard torx screws and is easy to work on.
 

JustMartin

macrumors 6502a
Feb 28, 2012
756
179
UK
It depends on how long you're going to keep the Mac for. My last iMac last me 5 or 6 years. As I couldn't foresee memory requirements that far out when I bought the 2012 model, I played it safe and got the 16. If you're only planning on keeping it two or three years, you could probably get by with less.
 

\-V-/

Suspended
May 3, 2012
3,297
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This is extremely out of date information. You do not need suction cups any more, you just need a guitar pick (cheap) or the official cutting tool ($10) to cut the tape holding the display on. This takes about 10 minutes. Replacing the screen requires fresh double sided tape that can be bought from anywhere (cheap) or from ebay/another supplier for the official Apple pieces (a few dollars).

The internal layout is simple and elegant and uses standard torx screws and is easy to work on.
Yeah, just looked at iFixit. Thanks.
 

CoMoMacUser

macrumors 6502a
Jun 28, 2012
674
3
It depends on how long you're going to keep the Mac for. My last iMac last me 5 or 6 years. As I couldn't foresee memory requirements that far out when I bought the 2012 model, I played it safe and got the 16. If you're only planning on keeping it two or three years, you could probably get by with less.
Agreed. I've been using this strategy since the mid-1990s with Windows and then Mac.
 

MartinAppleGuy

macrumors 68020
Sep 27, 2013
2,243
888
RAM pressure? That is more of a concern when surfing the intertubes for Lolcats, I think...
RAM pressure is a concern for everybody. Green indicates you are not pushing the system RAM, amber suggests the RAM is being tasked and exhausted, and red suggests the RAM is full and the system need to write to disk. With me having over 80 apps open at one time, the RAM pressure was still green with 8Gb for me, it never touched swap, and it hadn't even got to the stage of clearing App Cache/compressing RAM. The only way I see someone using more than 8Gb of RAM (even in the next few years) is through the use of VM's. I truly cannot push my system RAM over 50%, with everything open, or exporting a very complicated 1hr 40m video that once exported was 10.5Gb.
 

jaxhunter

macrumors regular
Dec 14, 2012
118
14
Maryland Eastern Shore
I get what you're saying I just have never heard it referred to as "pressure". Utilization, bandwidth, throughput, sure, but not pressure. Typically only fluids can be pressurized whereas electrons and data cannot.

Mostly, I was just trying to make a joke using the reference of the Internet being a serious of tubes designed for the delivery of Lolcats.

A point of clarification though: the computer is almost always writing to the disk cache it is just doing so at a much lesser degree sometimes. It doesn't show as a degredation to system performance until the writes exceed the flow capacity of the disk cache. Prior to that point the system never has to wait for the data to be writen or read from the disk cache and so performs at optimal speeds. Once you exceed that bottleneck then you will experience slowdowns as the system waits for space in the disk cache.
 

nzalog

macrumors 6502
Jul 25, 2012
277
2
I currently have 24gb ram on my 27" iMac late 2013 and I'm still facing page out..

look like 32gb ram is the way for me.
You don't know how computers work, don't give advice.

Paging is not an accurate indication of not enough ram. The kernel puts some things in swap no matter how much free ram you have. Yes, swap is generally for virtual memory when you are out of memory but it's not the only purpose. As others have mentioned memory pressure is what you should be looking at.

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Hi, i'm looking for iMac 21 2013. I use Chrome and Xcode mostly. Is 8GB ram enough or do i need 16GB ram if i currently have 4GB of page outs and 680MB of swap used in my MBP with 8GB ram? How much ram will you choose?
Depends on what you plan to do with it, I went with 16GB because I regularly run multiple VM's and memory is the most important thing those require to run smoothly. For xcode and chrome 8gb should be more than enough.
 

SaSaSushi

macrumors 601
Aug 8, 2007
4,084
479
Takamatsu, Japan
Interesting, and entirely unsurprising poll results. :)

Yes, the iMac is not entirely non user serviceable, but do you really want to risk voiding Apple's warranty in order to save a few dollars by doing that annoying surgery on a brand new machine?

I'm personally reserving that for when the AppleCare runs out on my own iMac and I upgrade the PCIe SSD in a few years.

I got my 27" iMac with 16GB from Apple so that when I upgraded to the full 32GB there was nothing to remove/replace. If the 21" had the user-accessible RAM compartment like its big brother than it would be a no-brainer: Buy with 8GB and update the other 8 on your own.

I'd go with 16GB. I don't believe in too much RAM. The need for RAM is only going to increase in the future and it will also increase the resale value of the machine if you ever decide to sell it.