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1.35 V & 1.5 V RAM for late 2013 iMac's
- Thread starter jobinho
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Hi NeoCracer,
Just to clarify, you are running the latest 2013 Haswell iMac? I have this same ram (32gb total) here and was concerned that it might not run on my new iMac which is due to arrive next week.
I have been looking into this too. I have ordered an iMac (delivery tomorrow) and have 32GB of Kingston DDR3 1600mhz pnp CL9 1.5v ram.
Apple do have a memory specification doc: http://support.apple.com/kb/HT5908
It states:
You can use any small-outline dual inline memory modules (SO-DIMMS) that meet all of these criteria:
PC3-12800
Unbuffered
Nonparity
204-pin
1600 MHz
DDR3 SDRAM
You can use RAM module sizes of 4 GB or 8 GB in each slot. Memory sold by the Apple Online Store is guaranteed to be compatible with your Macintosh.
DIMMs with any of the following features do not work in iMac (27-inch, Late 2013) computers:
Registers or buffers
PLLs
ECC
Parity
EDO RAM
Going by this, I think 1.5v should be fine
Yes, I'm running the 2013 Haswell iMac and the ram is running great! No problems whatsoever!
Thanks NeoCracer, my iMac should be here in a few days so will update here on my ram experience also
For those whom use 1.5v on iMac Late 2013 will probably having kernel panic error after few hours of intensive usage. I installed 32GB, 2 different batches of 1.5v, Kingston KVR16S11/8 & KTA-MB1600/8G (Equivalent Apple). Both freeze after few hours. Now Im testing on 32GB 1.35v Crucial RAM. Last weekend, I was running 16GB 1.35v Apple RAM + Crucial RAM without any issue. I also remember that I used 32GB Kingston KVR16LS11/8 on BTO iMac Late 2013 without any issue few weeks ago. I believe only L 1.35v RAM will have no issue with iMac Late 2013.
Okay, got my iMac - i've installed 32gb of Corsair Vengeance ram.
The iMac came with 10.8 originally - played around with it and within 30 minutes the iMac just simply restarted on it own.
So.. was a bit bothered by that - anyway I downloaded Mavericks then the iMac's SMC update, played starcraft and sim city for a while and since then there has been no unexpected crashes or kernel panics as yet under Mavericks..
Did the apple hardware test also - no problems detected.
What do you guys think? the unexpected restart is giving me a big question mark.
Anyway, what a great machine!
The iMac came with 10.8 originally - played around with it and within 30 minutes the iMac just simply restarted on it own.
So.. was a bit bothered by that - anyway I downloaded Mavericks then the iMac's SMC update, played starcraft and sim city for a while and since then there has been no unexpected crashes or kernel panics as yet under Mavericks..
Did the apple hardware test also - no problems detected.
What do you guys think? the unexpected restart is giving me a big question mark.
Anyway, what a great machine!
hi cpc6128, are you using
http://www.amazon.com/Corsair-Venge...600C10/dp/B0076W9Q5A/ref=cm_cr_pr_product_top
If yes, the RAM is 1.5v & I believe you will face an issue after few hours of usage. I tested 2 sets of 1.5v Kingston RAM & gave me problem. Only 1.35v no issue.
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This is definitely not true.
I have 1.5V G.Skill (this model) sticks in my iMac, alongside the factory sticks (2x 4GB + 2x 4GB) and I have zero issues. This includes both compiling software, running VMs and some gaming: the machine is being "stressed".
Given all of these posts where people keep getting RAM stuck, I'd be more tempted to say it's just user error (static damage, not seated correctly, etc) than a voltage issue.
Yes it's the 1.5V Corsair Vengeance - I have had the iMac running the whole time since my last post and ran memtest for a few hours (all passed), sim city in the background etc.. no crashes, unexpected restart or Kernal Panics since updating to Mavericks.
Would it be safe to say it's all good - Ram wise?
Also had some strange speaker knocking sounds that happens when i have the sim city launcher window up - probably a bug.
Any other stress app you guys recommend?
Would it be safe to say it's all good - Ram wise?
Also had some strange speaker knocking sounds that happens when i have the sim city launcher window up - probably a bug.
Any other stress app you guys recommend?
You probably won't see the problem when you don't upgrade to 32GB. If static damage or RAM not seated correctly, the iMac won't last for few hours of usage before it starts to crash, sometimes black out or white screen for no reason.
In 2010 iMac, there were many cases when people upgrade to maximum RAM.
See https://discussions.apple.com/thread/2567907?start=0&tstart=0
That's too much "probably" for my tastes. Given a large sample size, there's bound to be plenty of RAM failures/RAM damage/etc. I still believe the 1.35V vs. 1.5V theories lack evidence.
I just upgraded my late 2013 iMac with 32gb of Kingston HyperX 16GB Kit 1866MHz DDR3 PC3-14900 Non-ECC CL11 1.35V Low Voltage. Here is the link to Amazon Kingston HyperX Memory.
Another benefit is this RAM is running in my iMac @1867MHz. I've been running for over 2 weeks without an issue. It also fit the slots perfectly.
Another benefit is this RAM is running in my iMac @1867MHz. I've been running for over 2 weeks without an issue. It also fit the slots perfectly.
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I tested 3 units of iMac 2013. Only (8GBX4) Kingston KVR16LS11/8 1.35v & (8GB x4) Crucial 1.35v have no issue. Both KVR16S11/8 1.5v & KTA-MB1600/8G 1.5v failed with kernel panics after 2hrs plus.
Kingston website recommends KTA-MB1600L/8G 1.35v
http://www.kingston.com/us/memory/s...le_-_iMac_Intel_Core_i5/i7_27-inch_(Late_2013)
Crucial website recommends CT4951624 16GB kit (8GBx2) 1.35v (4 users have positive reviews)
http://www.crucial.com/store/mpartspecs.aspx?mtbpoid=81CE351CA5CA7304
OWC website recommends 1600DDR3S32S 1.35v
http://eshop.macsales.com/item/Other World Computing/1600DDR3S32S/
OWC website only recommends 1333DDR3S32S 1.5v for iMac 2011.
There must be a reason why these companies refuse to use RAM 1.5v for iMac 2013.
Kingston website recommends KTA-MB1600L/8G 1.35v
http://www.kingston.com/us/memory/s...le_-_iMac_Intel_Core_i5/i7_27-inch_(Late_2013)
Crucial website recommends CT4951624 16GB kit (8GBx2) 1.35v (4 users have positive reviews)
http://www.crucial.com/store/mpartspecs.aspx?mtbpoid=81CE351CA5CA7304
OWC website recommends 1600DDR3S32S 1.35v
http://eshop.macsales.com/item/Other World Computing/1600DDR3S32S/
OWC website only recommends 1333DDR3S32S 1.5v for iMac 2011.
There must be a reason why these companies refuse to use RAM 1.5v for iMac 2013.
But elithrar disagrees. We got no prove that iMac 2013 needs 1.35v.
Below link, this user posted at Apple forum recently, having same issues as me. Both of us using KTA-MB1600/8G 1.5v RAM on iMac 2013. At his thread, someone mentioned that he had several machines with the same issues & Kingston told him to use 1.35v modules rather than 1.5v.
https://discussions.apple.com/message/23582522#23582522#23582522
Corsair also recommends 1.35v
http://www.corsair.com/us/memory-by...r3l-sodimm-memory-kit-cmsa8gx3m1a1600c11.html
All certified Mac RAMs for late 2013 are rated @ 1.35v and CL11. I am waiting for my kingston HyperX Lovo CL9 -1.35V to confirm that CL9 can run smoothly.
Some users managed to install 1866MHz RAMs in their late 2013 but Apple says the maximum bus speed is 1600MHz.
Long story short, never take what Apple says seriously... I'd rather follow Intel recommendations.
sigh.. I got a kernel panic..
Will be swapping back over the original ram and running the iMac to be sure it's nothing else but the 1.5v ram.
Was playing Sim City for about 2 hours then it just hanged then a grey screen with a kernel panic message.
Did the problem appeared with the Original Ram from Apple?
I'm having too kernel panics since I upgraded the memory to Crucial 32Gb ram
specs:
Module Size: 2x16GB kit (8GBx4)
Package: 204-pin SODIMM
Feature: DDR3 PC3-12800
Specs: DDR3 PC3-12800 • CL=11 • Unbuffered • NON-ECC • DDR3-1600 • 1.35V • 1024Meg x 64 • lead free • halogen free • for Mac
I've done terminal memtest, Apple Diagnostic Hardware test, diglloydTools memory test no one give me an error, but after a few hours it restart by itself and give me report with Kernel Panic
"BSD process name corresponding to current thread: kernel_task"
Regards,
UnfraGile
Last edited:
Crucial confirmed an issue with their Mac Compatible RAMs. Contact them for more info.
