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iMac Haswell + CL9 RAM @ 1.35V

Are there any benchmarks of the Kingston hyperx lovo 1600 vs g.skill ripjaws 1866

Just ordered the ripjaws and wondering how timings effect performance/if at all
 
CrAzYLiFe said:
Are there any benchmarks of the Kingston hyperx lovo 1600 vs g.skill ripjaws 1866

Just ordered the ripjaws and wondering how timings effect performance/if at all
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Got them !! Wait for me a couple of days so I can go back home and run some benchmarks ;)
 
Can't wait to see the results! Benching with 16Gb first would be awesome so I can compare with jaguarxl's ripjaws performance.
 
If you drop the cash on 32GB of RAM, you should've tried the 1866MHz CL10 Crucial Ballistix Sport kit instead. It's the fastest of the 16GB SODIMM kits around, and it has the most professional name of all RAM modules, too.

Crucial said:
Unleash the victor in your system. Designed to pack the power of Ballistix® into your gaming laptop, all-in-one, or mini ITX motherboard, Crucial® Ballistix® Sport SODIMMs arm your system with the speed, power, and efficiency to own your opponents from anywhere.
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Oh, man. :rolleyes: If you combat large datasets, the RAM is so fast that you can own them now – in case they weren't your property to begin with. Crucial does have quality RAM and this one is not only faster than the regular one but also the fastest of all 1866MHz kits, for all I care. Who the **** is Victor, though?

It's 1.35V as well, and it should also work in Haswell Macs (the 1866MHz CL11 Kingston HyperX Plug'n'Play is known to work even in most Ivy Bridge Macs already).
 
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Giuly said:
If you drop the cash on 32GB of RAM, you should've tried the 1866MHz Kingston HyperX Plug'n'Play kit instead.

It's 1.35V as well, and it should also work in Haswell Macs (it is known to work in most Ivy Bridge Macs already).
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I thought of it but it's a CL11 not CL9. Lower timing from what I noticed is usually more expensive than faster bus speed.
 
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IA64 said:
I thought of it but it's a CL11 not CL9. Lower timing from what I noticed is usually more expensive than faster bus speed.
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Think about it. MHz tell you how often something happens per second. Latencies tell you how many steps it takes until the RAM is ready to read or write, and with faster MHz, each of those steps requires less time as well. 1600MHz CL9 has really the same latency as 1866MHz CL11 if you measure the CL in nanoseconds, but the faster bus speed is beneficial, too.

And the Crucial kit is 1866MHz CL10, not CL11 like the Kingston. But 1866MHz CL10 is, according to the JEDEC specifications, optional and so it may or may not work on a Mac. However, even the 1866MHz HyperX kit would at least not be slower than the 1600MHz counterpart.
 
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Giuly said:
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Think about it. MHz tell you how often something happens per second. Latencies tell you how many steps it takes until the RAM is ready to read or write, and with faster MHz, each of those steps requires less time as well. 1600MHz CL9 has really the same latency as 1866MHz CL11 if you measure the CL in nanoseconds, but the faster bus speed is beneficial, too.

And the Crucial kit is 1866MHz CL10, not CL11 like the Kingston. But 1866MHz CL10 is, according to the JEDEC specifications, optional and so it may or may not work on a Mac. However, even the 1866MHz HyperX kit would at least not be slower than the 1600MHz counterpart.
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I have to disagree :


CAS latency (and the other timings as well) are in units of clock cycles. So CAS 9 means 9 clock cycles. Clock cycle time is dependent on frequency, so :

1) 1600MHz = 1,600M cycles/second = 0.625ns / cycle
2) 1866MHz = 1,866M cycles/second = 0.535ns / cycle

So the timings for each, now expressed in ns, are:

1) 9 - 9 - 9 = 5.63ns - 5.63ns - 5.63ns @1600MHz
2) 11 - 11 - 11 = 5.88ns - 5.88ns - 5.88ns @1866MHz

Shorter intervals are better for timing (less time to wait means it's faster, which is why lower timings are better).

1600MHz CL9 will be faster than 1866MHz CL11 but then again, only benchmark softwares would notice the difference.
 
burningrave101 said:
This G. Skill 8GB 1600Mhz CL9 stick looks to be on sale for $54.99:

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231704

Two of them is $50 cheaper than the same speed and CAS 16GB kit:

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231705

I'm not sure what the difference is though in the model numbers since one kit is F3-1600C9S and the other is F3-1600C9D. Hopefully both are Late 2013 iMac compatible.
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Both are same memory. The difference is the kit. F3-1600C9S for single chanel (single module) and F3-1600C9D for dual chanel kit (two modules).

:D
 
IA64 said:
I have to disagree :


CAS latency (and the other timings as well) are in units of clock cycles. So CAS 9 means 9 clock cycles. Clock cycle time is dependent on frequency, so :

1) 1600MHz = 1,600M cycles/second = 0.625ns / cycle
2) 1866MHz = 1,866M cycles/second = 0.535ns / cycle

So the timings for each, now expressed in ns, are:

1) 9 - 9 - 9 = 5.63ns - 5.63ns - 5.63ns @1600MHz
2) 11 - 11 - 11 = 5.88ns - 5.88ns - 5.88ns @1866MHz

Shorter intervals are better for timing (less time to wait means it's faster, which is why lower timings are better).

1600MHz CL9 will be faster than 1866MHz CL11 but then again, only benchmark softwares would notice the difference.
Click to expand...

The data transfer on the n+1th cycle (and all successive cycles) is shorter on 1866MHz, too, which neglects the fact that the data is ready earlier.

The correct formula for latency is (CAS / I/O bus clock) x 1000MHz, so it's

(9/800)x1000 = 11.25ns
(11/933)x1000 = 11.786ns
(10/933)x1000=10.718ns

The Geekbench score for 1866MHz CL11 is however slightly higher than 1600MHz CL9 because this way of thinking only applies to non-sequential reads and again, the Crucial kit with 1866MHz CL10 is faster than both.
 
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Giuly said:
The data transfer on the n+1th cycle (and all successive cycles) is shorter on 1866MHz, too, which neglects the fact that the data is ready earlier.

The correct formula for latency is (CAS / I/O bus clock) x 1000MHz, so it's

(9/800)x1000 = 11.25ns
(11/933)x1000 = 11.786ns
(10/933)x1000=10.718ns

The Geekbench score for 1866MHz CL11 is however slightly higher than 1600MHz CL9 and again, the Crucial kit with 1866MHz CL10 is faster than both.
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It's the same formula. You're calculating the latency for one single data rate l not dual one thus your numbers are doubled.

And it's not x 1000MHz it's x 1000 [ 1/ ( 10^6 x 10^-9 ) ] -> 1 / ( nano x mega ) -> 1/10^-3 = 1000

@ Jaguarxl

If you have bootcamp, can you please check CPUz and post the operating latency of your RAM modules ?
 
May I request those kindhearted individuals in our forum to start a thread to regarding those RAM models that work and don't work for the latest iMac (Haswell)?

It will be beneficial to our community to lay this issue to rest by giving a proper guideline, such as maximum RAM, latency, speed, etc.

Thank you!
 
minimalism said:
May I request those kindhearted individuals in our forum to start a thread to regarding those RAM models that work and don't work for the latest iMac (Haswell)?

It will be beneficial to our community to lay this issue to rest by giving a proper guideline, such as maximum RAM, latency, speed, etc.

Thank you!
Click to expand...

I started a short summary in the first post and waiting for more input to finish the table.
 
Well my 1866 cl10 rip jaws arrived at work today! To bad I'm on guard duty.

I'll post some results tomorrow, what's some good bench marking tools/ memory testing programs to test it all out with?

If all goes well I'll be ordering another 16gb!
 
I just bought the Crucial Ballistix Sport SODIMM 16GB Kit (8GBx2) DDR3 1866 I will be recieving it tomorrow...anyone else using this kit?
 
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