G-Skill Ripjaw F3-12800CL7D DDR3 1600

dannyboyee82

dannyboyee82

dannyboyee82

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Ok, so when it comes to memory, I'm completely baffled. I bought this memory for my new i7 rig about a month ago, something that I ignored was the fact that it is running at 1333mhz and not 1600mhz. Ignore my sig as I've returned all setting to stock speeds for now, when it was overclocked the memory was running at 1053mhz I think.

Is 1333mhz what it is supposed to be at? When I try to set it to 1600, it won't have it.. leads to blue screen crash before I even get to windows.

Help is appreciated, and thanks in advance.
 
1333MHz and I think 9-9-9-24 or 10-10-10-24 is what it runs at if you just stuff the sticks in.

Are you overclocking it manually or using the XMP settings?
 
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Weird how they say it's 1600mhz when it runs at 1333mhz!

Yeah, I was using the XMP.. I have no idea how to do it manually, don't want to try without help from people on here for fear of screwing things up!

I'm fine with overclocking CPU's, done that for a while now but memory confuses me!

Cheers.
 
No one actually does memory over 1333MHz, everything higher is an overclock.

They test it to be sure it works but it's an overclock all the same.
 
The memory should work fine at 1600 7-7-7-24 2T 1.6V (XMP Profile). That's what it's rated to! I guess the CPU Base Clock is 133MHz, as anything more will increase the memory speed beyond 1600 (133x12).
 
As Core i5 and i7 CPUs have the memory controller integrated, the memory speeds are set directly by the CPU base clock.

Obviously standard i5/i7s use a 133MHz base clock, and a CPU multiplier. My i5 runs at 133x20=2.66GHz, and your i7 runs at 133x21=2.8GHz. Memory runs at the same base clock as the CPU, using a Memory multiplier. Core i5 allows x6, x8, and x10 memory multiplier. i7 allows those plus x12.

So, max *stock* memory speeds of the i5 are 1333 (133x10), and i7 are 1600 (133x12).

I can run memory at 1600, but I have to raise my CPU base clock to 160MHz to do this, due to the x10 memory multiplier limit. So CPU could be 160x17, and memory 160x10. If I was to overclock the CPU again, to 180MHz, this would bump the memory speed to 1800MHz at x10.

I would therefore have to drop the memory multiplier to x8 (giving 1440MHz) or else loosen up the latency timings to get the memory stable.

When you enable the XMP, it may set 133x12 (for i7) or 160x10 (for i5). Not sure which one, as I only have the i5! Either way, when you start upping your base clock you will have to keep an eye on memory multipliers and memory speed. Potentially setting XMP for 1600, but increasing the base clock will run the memory >1600, resulting in an unstable system.

Makes sense?
 
I guess use whatever base clock you want. But be sure to decrease the memory multiplier each time so that the memory speed is always below 1600MHz. Sure you can figure it out ;)
 
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