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New iMac 27", RAM which brand?

A

Adamx

macrumors member
Original poster
Mar 11, 2011
40
2
Hello everybody,
Soon I'm going to order an Imac 27" 3.4ghz with 2gb Geforce.
I'm still on hold to get a video from OWC in order to upgrade my future machine with an 240GB Mercury EXTREME Pro 6G SSD 2.5"OWC SSD.

Meanwhile I'm going to upgrade the ram with a 32Gb (4x8Gb modules) so my FCP is going to be happy with it once for all.

Which brands is the best pick for you guys?
OWC, Crucial etc.?

What is the main differences at the end? Just the price?
What Brand are you going to use in your machines people?

Thanks a lot! :)
My english is crap btw, excuse me in advance! lol
 
I swear by Crucial, great prices, excellent customer service and a lifetime warranty...The scanner app on the site will identify the correct modules for you.

Others like Kingston, but a cautionary word...If you do buy from them avoid the "Value" RAM...It's not up to the job.
 
I just ordered 32GB from crucial. only ~$160. better than the $725 apple wanted (aus)
 
I went for the Kingston HyperX. It's the only CL9 I could find. Also, the only one with heat spreader. Little more expensive than the CL11s out there but still much cheaper than Apple RAM.
 
Sorry this post just reminded me of the 1800 Contacts commercial. “MY BRAND!”

I got the Kingston hyperx stuff but I was just grabbing whatever was cheapest.
 
Macman45 said:
I swear by Crucial, great prices, excellent customer service and a lifetime warranty...The scanner app on the site will identify the correct modules for you.

Others like Kingston, but a cautionary word...If you do buy from them avoid the "Value" RAM...It's not up to the job.
Click to expand...

Why? I just bought 32 gigs of those ?? :(

----------
Peakbagger said:
I went for the Kingston HyperX. It's the only CL9 I could find. Also, the only one with heat spreader. Little more expensive than the CL11s out there but still much cheaper than Apple RAM.
Click to expand...

Doesnt it have to be 11 CL? arcording to owc its cl 11!
 
Fantola said:
Why? I just bought 32 gigs of those ?? :(

----------



Doesnt it have to be 11 CL? arcording to owc its cl 11!
Click to expand...

No, it can be CL9, or even CL 7, but that would most likely only be available at 1333MHz. The SODIMMS contain a table containing the latencies for various clock speeds. The CPU's memory controller reads the info, and sets its frequency at the highest speed that both it and the SODIMM can handle. It then sets the the RAM's CL timing for that speed according to the table info.
 
Kingston HyperX
KHX16S9P1K2/16
16GB (2 x 8G)
DDR3 1600
Cas Latence 9
Voltage 1.5V
http://www.newegg.com/Product/Product.aspx?Item=N82E16820104317&Tpk=KHX16S9P1K2/16

It's the only memory of this FSB and size with the lowest Cas Latence of 9.

It works with 2012 Macs.

Priced at $145 for 16GB so you'll be spending $290 for 32GB.

In my case I got G.SKILL F3-1600C10D-16GSQ as it's the cheapest Cas Latency 10 memory at $70 for 16GB so I'll be spending $140 be spending $140. It works with 2011 and 2012 Macs.
 
drambuie said:
No, it can be CL9, or even CL 7, but that would most likely only be available at 1333MHz. The SODIMMS contain a table containing the latencies for various clock speeds. The CPU's memory controller reads the info, and sets its frequency at the highest speed that both it and the SODIMM can handle. It then sets the the RAM's CL timing for that speed according to the table info.
Click to expand...

So why is it better to have a lower CL?
 
Fantola said:
So why is it better to have a lower CL?
Click to expand...



With asynchronous DRAM, the time delay between presenting a column address and receiving the data on the output pins is constant. Synchronous DRAM, however, has a CAS latency which is dependent upon the clock rate. Accordingly, the CAS latency of an SDRAM memory module is specified in clock ticks instead of real time.

Because memory modules have multiple internal banks, and data can be output from one during access latency for another, the output pins can be kept 100% busy regardless of the CAS latency through pipelining; the maximum attainable bandwidth is determined solely by the clock speed. Unfortunately, this maximum bandwidth can only be attained if the data to be read is known long enough in advance; if the data being accessed is not predictable, pipeline stalls can occur, resulting in a loss of bandwidth. For a completely unknown memory access (AKA Random access), the relevant latency is the time to close any open row, plus the time to open the desired row, followed by the CAS latency to read data from it. Due to spatial locality, however, it is common to access several words in the same row. In this case, the CAS latency alone determines the elapsed time.

In general, the lower the CAS latency, the better. Because modern DRAM modules' CAS latencies are specified in clock ticks instead of time, when comparing latencies at different clock speeds, latencies must be translated into actual times to make a fair comparison; a higher numerical CAS latency may still be a shorter real-time latency if the clock is faster. However, it is important to note that the manufacturer-specified CAS latency typically assumes the specified clock rate, so underclocking a memory module may also allow for a lower CAS latency to be set.
Click to expand...

http://en.wikipedia.org/wiki/CAS_latency#Effect_on_memory_access_speed
 
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