Memory and XMP Questions

I have the following G.Skill Ripjaws series in my build (2 x 4GB):
I had a couple of questions about the speed of the memory. I am very ignorant with this stuff and am new to building my own systems. Do I have to enable XMP to get the memory to 1600? Is there a way for me to test what the actual speed of the RAM is currently? If it is already running at 1600 (w/o me doing anything special in the BIOS), what would enabling XMP get me (would it change speed, voltage, timings?). Thank you!
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More about memory questions
  1. Hi, Try installing CPU-Z
    There you have a memory tab where you can see the RAM speed and timings. For 1333 CPU-Z will show 667 and for 1600 will read 800.
    There is also a SPD tab, where you can read the values set by the manufacturer for default and XMP.
    By enabling XMP, the system would automatically set the values specified for XMP.
  2. Hello,
    Thank you. I installed CPU-Z and indeed it reads 800, which is good. The CAS latency and other timings are different from what I expected though. What exactly does enabling XMP change, other than memory timings? For instance, does it increase the base clock (effectively OCing the CPU as well)? Does it remove any power saving features?
    For instance, I think I've read somewhere that enabling XMP turns off several features such as Turbo mode and things related to energy savings or sleep steps. Is this true? Any help is appreciated. Again, thank you very much!
  3. XMP stands for Extreme Memory Profile. It is the profile that the manufacturer created for your ram. They chose the frequency, timings, latency, etc. Just load it so you don't have to worry about doing it yourself.
  4. Everyone above provided great info. To sum it up, XMP Profile adjusts DRAM Frequency, Timings, and Voltage. For extreme kits like DDR3-2133+ 16GB+, they may have XMP 1.3, which has profile information for IMC Voltage (memory controller). It is only effective for newer Intel systems, so for example, if you purchase a RipJaws X Z77 DDR3-2400 32GB memory kit, it will have a 1.20V-1.25V VCCSA Voltage change to stabilize the CPU memory controller for the RAM. This is exactly why we recommend using only motherboards on our qualified motherboard list. It allows for easy, quick, hassle free installation for extreme performance. Otherwise, manual settings and tweaking is required if you choose to use other hardware. In other words, if you use it with an AMD system, manual CPU memory controller (CPU-NB Voltage) adjustment is necessary since the XMP Profile was not designed for AMD CPUs or the motherboard.

    For the kit you have, it is very basic, so enable XMP and everything should be ready to go at rated specifications.

    Thank you
  5. Thank you for all of your help, I sincerely appreciate it. Do any of you have some advice regarding how to test for stability after I enable the XMP profile (or I guess any memory OC in general)?
  6. You can download a stress test like Prime95. It will put your computer at 100% load, so if there is any problem, it should error fairly quickly.

    Thank you
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