Comparing Speed to Cas Latency to Savings

[Dougx1317]

My first thread got a lot of heat for not having the rest of my system specs figured out. I have since corrected that problem. I was going to get following Ripjaws RAM at 1600Mhz, CL 7: http://www.newegg.com/Product/Product.aspx?Item=N82E16820231279 (1600Mhz, CL 7-7-7-24, No Savings)

But then I found these two combos with my chosen motherboard that could save me as much as $45. They are all the same brand and voltage. They also all have higher speed and higher CL. How will the change in speed and CL effect the overall speed? Is it worth the savings to get a combo or should I stick with my original RAM?

http://www.newegg.com/Product/ComboDealDetails.aspx?ItemList=Combo.289971 (1866Mhz, CL 9-9-9-24, Saves $45)
http://www.newegg.com/Product/ComboDealDetails.aspx?ItemList=Combo.289972 (2000Mhz, CL 9-9-9-27, Saves $20)

i7 860
Gigabyte P55-UD3R
Xigmatek Dark Night S1283
ATI 4890
Velociraptor
750W FSP PSU
Planning to overclock moderately

 

[TheViper]

Go for the bigger savings.

 

[Dougx1317]

So, you don't think that I will see a performance difference? Is 1600Mhz at CL 7 roughly the same as 1866Mhz at CL 9? Or is it possible to lower the speed to 1600Mhz and tighten the timings to 7? How much impact does RAM speed even have on a system?

 

[TheViper]

Your final question is the most relevant. Unless you are overclocking or the speed difference is huge, you really wont' even notice a difference in speeds (clock or timings).

Now speed itself will have a bigger impact than timings. So 1866 CL9 will see better performance than 1600 CL7.

And yes, you can play with the speed and timing to the degree permitted by the motherboard BIOS, CPU, RAM itself, voltage and such.

 

[Dougx1317]

Now speed itself will have a bigger impact than timings. So 1866 CL9 will see better performance than 1600 CL7.

So, the 1866Mhz CL 9 with have the same or better results than the 1600Mhz CL 7? I thought the RAM speeds only mattered up to a certain point depending on the CPU. For the i7 860, I think it was 1333Mhz before it lost the 1:1 Ratio. Will overclocking compensate for this, or am I completely wrong on this point?

Unless you are overclocking or the speed difference is huge, you really wont' even notice a difference in speeds (clock or timings).

Will it matter if I plan to overclock? I was hoping to hit 4Ghz and have RAM performance to compliment it.

 

[TheViper]

Sorry, I was speaking in general there and not based on your CPU.

High RAM speeds and low timings are what you want if you plan to overclock as they allow breathing room needed to reach those high CPU speeds.

 

[Dougx1317]

Alright. I'll go for the 1866Mhz CL 9 and save $45. I'm a little concerned about the low reviews, but my motherboard is on the RAM's support page. Thanks for your help.