4266 MHz XMP Won't boot.

I'm trying to run my ram at I'ts rated speed with XMP but It just Isn't working on a 5.0GHz 7700k. However when I lower the Dram frequency to 4133MHz It works fine. Any reason why this Is happening?

 

Try bumping up the ram voltage a notch.

 

Drop the RAM timings too slightly if voltage isn't enough

 

It's currently at 1.408v not sure If going past 1.4v on Dram would damage my components.. Will try 1.42v though for science

EDIT: 1.42v still doesn't work even though my motherboard Is listed on the rams QVL page.....

The ram Is rated at CL19 wouldn't dropping timings further cause more Issues?

This Is the one I'm using.
http://gskill.com/en/product/f4-4266c19d-16gtzkw

 

try your cpu at stock speeds if it works nothing wrong with the ram

 

Chances are its the CPU.
I can run my Ram at 3600MHz when my CPU is at 4.6GHz.
But I am down to 3333MHz when my CPU is at 4.7GHz.
Such is life, especially if you are pushing the boundaries anyway.

The memory controller is on the CPU, it has its limits.
Make a choice.

 

Chances are its the motherboard. Many of the new kaby lake boards have a max of 4133mhz that you are being stuck at

And actually the asus maximus ix forumula board has a max of 4133mhz and you have the maximus ix apex so im assuming its probably the motherboard chipset limit

 

Probably wise to read up on his motherboard.

 

Yeah. The asus maximus ix forumla has a limit of 4133mhz. He has the ix apex im betting it has the same limit

 

Its not a limit, its based on module availability and what they had time to test.
When a motherboard is released the currently available modules that have been tested are put in the QVL.
If the QVL gets updated it tends to be a while later, often not at all.
It does not define the maximum memory speed the board can use.

The Maximus series are very capable.
The CPU also has to be capable, luckily Kaby lake are, but when highly overclocked you often have to drop memory speed to maintain the CPU overclock.

Chances are it will work fine if he drops his CPU overclock by 100MHz.

 

Try system agent, vccio, cpu standby voltages.

 

Not guaranteed to work. Try 1.25~ system agent.

 

What's your VCCIO set at?

Also might want to read this thread.

 

What they said. Can't expect such RAM frequenzies to run at your CPU's stock voltages in the other fields but core. You're doing extreme overclocking (no matter if it comes via XMP or not), say goodbye to running stock voltages at all times.

 

The Issue Is I'm not getting the advertised speed even at stock cpu clocks and It was advertised that the ram would work straight out of the box with XMP.

Doesn't work at stock cpu speeds.

Doesn't work at stock cpu speeds. I guess I'll just stick with 4133MHz on the ram and 5.2GHz On cpu for now.

My System agent and VCCIO voltages are both over 1.35v around 1.37 and they still don't work.

 

Did you try mixing and matching the RAM modules in your mainboard's slots? Can make a difference, especially with high frequency RAM. Besides that usually voltage raising on VCCIO, SA and the RAM should help. If it doesn't work you could always try to RMA your RAM.

 

Unfortunate.
It is worth getting in touch with the ram mfr in case you have fringe case ram, they will likely give you another shot at it.

 

I got mine shipped from the US via Newegg so I doubt G.Skill would send me a new one. I'll try contacting them anyways.

Thanks.

 

Waste of time.
Those speeds aren't guaranteed(the ram is guaranteed to run at those speeds) because the IMC of every CPU varies.

Your CPU's memory controller isn't strong enough or you lack the correct tweaking.

 

I guess It's the CPU's memory controller since the ram Is advertised to work at 4266MHz out of the box using xmp with no additional tweaking on my end and that doesn't work even at stock Cpu speed. But 4133MHz works for me @ 5.2GHz 1.42 vcore so I guess I'll live with It for now.