Question about RAM upgrade

UltraFireFX

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Dec 16, 2013
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So I want to upgrade my total RAM from 8GB (2x4GB) to 16GB, this is because I often have many programs open (sometimes alpha/beta games, which are often poorly optimized, and many tabs in my browser) and my task manager shows that my RAM is often clocked out when I experience latency but not my CPU, HDD or network.

Currently I'm running 2 G.Skill Ripjaws 4GB DDR3 modules @ 803MHz (11-11-11-28), stock, I've heard that RAM won't work with other RAM modules if the CAS latency is not the same and if the clock speed on one is lower it will 'underclock' the other to match the lowest one.

So, now for my questions:
- Does anyone disagree my choice of upgrading? If so, why? I'd like to know.
- Is the above about RAM compatibility true? Is it a factor when upgrading RAM?
- Should I just get new RAM (4x4GB/2x8GB) or try to buy some matching RAM modules? If I do, I will have to ship matching RAM modules in from the USA (from NZ here) which will add to the price. Whereas I could get new modules locally for a much smaller margin.

Thanks for your time.

P.S. My CPU is an AMD FX-8350, my motherboard is a ASUS M5A78L-M LX PLUS.
 

UltraFireFX

Honorable
Dec 16, 2013
143
0
10,710


But even thought my current RAM is running at 803MHz, would that not affect the new ones?