NEW 5K iMac 27 - 1600 or 1867 Mhz RAM?

[AppleGuy1993]

The apple support page says that it's 1600 Mhz for the new 2015 model https://support.apple.com/en-us/HT201191

The Tech Specs page says it's 1867.

Not sure which 3rd party RAM to buy (planning on upgrading to 32GB)

Any suggestions?

 

[Liffey]

Yeah I'm wondering which 3rd party RAM to get as well. Would this still work? http://www.crucial.com/usa/en/imac-4*0ghz-quad-core-intel-core-i7-(27-inch,-late-2014)/CT6312882

 

[Alesc]

Yeah I'm wondering which 3rd party RAM to get as well. Would this still work? http://www.crucial.com/usa/en/imac-4*0ghz-quad-core-intel-core-i7-(27-inch,-late-2014)/CT6312882

If you take these, your memory will run at the speed of the slowest DIMMs, in that case 1600MHz.
If you want your memory running at 1866MHz, take these: http://www.crucial.com/usa/en/bls2k8g3n18aes4

 

[Liffey]

Hmm, Crucial says those aren't compatible with iMac.

 

[itfiend]

Hmm, Crucial says those aren't compatible with iMac.

May just not have updated site yet?

 

[gmanist1000]

Hmm, Crucial says those aren't compatible with iMac.

They're probably referencing the old version which had 1600MHz speed.

 

[Alesc]

Hmm, Crucial says those aren't compatible with iMac.

I have 4 of those running in my 2013 27" right now
The memory controller is in the Intel CPU, you can even put 2133MHz memory if you want.

Crucial is advising that because in previous iMacs, if you mixed the original "Apple " RAM (1600MHz CL11) with faster RAM (CAS9 or CAS10), the controller run all the modules at 1333MHz CAS9 or 10 to adapt the speed to the slower modules...

If you have time: https://forums.macrumors.com/threads/rimac-upgrading-ram.1812955/

 

[Liffey]

I think I'll wait until someone tests DDR4. Curious if that would work.

 

[MacVault]

Speaking of RAM, how much faster is DDR4 vs DDR3? In what situations would I really notice the difference? ie. video production? gaming? ??

 

[T'hain Esh Kelch]

Speaking of RAM, how much faster is DDR4 vs DDR3? In what situations would I really notice the difference? ie. video production? gaming? ??

Unless you run a rendering farm, not really.

 

[cynics]

Speaking of RAM, how much faster is DDR4 vs DDR3? In what situations would I really notice the difference? ie. video production? gaming? ??

 

[mosher]

i`ll be buying ddr4 for sure