CPU and RAM overclocking

[Garrett Tyrna]

Hello everybody, I was wondering if anyone knows why my I5 6600k doesn't allow my ram voltage to be at 1.35. I have CPU overclocked to 4.1, I don't know if I have to overclock further than this or if that even matters. it doesn't allow me to put on the xmp profile without it crashing. I have:
i56600k
z170pro gaming
4x4 corsair vengeance 16gb 300mhz 1.35v

thanks a lot for your time and knowledge!

 

[steffeeh]

Make sure you setup the following voltages:
- VCCSA (aka System Agent Voltage) -> 1.1V (Manual mode)
- VCCIO -> 1.1V
- VTTDDR -> half of the DRAM voltage

If this doesn't do it, try to actually up the memory from 3000MHz to 3200Mhz, and also change the timings to match the ones from a RAM kit with 3200MHz XMP from the same brand.
It sounds crazy, but this could be a compability issue more than an unstable overclocking. This has worked before. 3000MHz often seem to cause issues on Z170 and X99, which is why I always recommend 3200MHz instead.

Also, sometimes you need to overclock the CPU to a certain frequency to make higher bandwidth RAM to work, 4.1GHz might be too little. But try the compability check first.

 

[Garrett Tyrna]

Make sure you setup the following voltages:
- VCCSA (aka System Agent Voltage) -> 1.1V (Manual mode)
- VCCIO -> 1.1V
- VTTDDR -> half of the DRAM voltage

If this doesn't do it, try to actually up the memory from 3000MHz to 3200Mhz, and also change the timings to match the ones from a RAM kit with 3200MHz XMP from the same brand.
It sounds crazy, but this could be a compability issue more than an unstable overclocking. This has worked before. 3000MHz often seem to cause issues on Z170 and X99, which is why I always recommend 3200MHz instead.

Also, sometimes you need to overclock the CPU to a certain frequency to make higher bandwidth RAM to work, 4.1GHz might be too little. But try the compability check first.

thank you very much I will try this. but I have a couple of questions for you. if my RAM is rated for 3000 MHz and I put it to 3200 is that dangerous to my RAM? also, I checked the motherboard compatibility list and it says that my ram is compatible, the CMK serial code. If it is a compatibility issue which is what it seems like, then I don't understand how this can be.

 

[steffeeh]

No, the RAM frequency the sticks are sold at are just an XMP profile, that won't be used until you've enabled XMP in BIOS - the RAM can run at multiple speeds, both lower and higher, given that you adjust timings and the DRAM voltage accordingly (to a certain limit of course).
This isn't dangerous for the RAM sticks as long as the temperatures are good on both RAM and CPU (which is no problem for DDR4 RAM), or as long as the DRAM voltage is below 1.5V (specified by Intel) as it can otherwise degrade the memory controller on the CPU. Though most people no longer feel comfortable above 1.4V, as it's the highest voltage setting found in XMP profiles.

The only uncomfortable thing is that if you try out a settings that goes unstable right when the computer boots, then BIOS won't boot since it can't find the RAM, and then you need to pick out a battery (called CMOS) from the motherboard to reset everything in BIOS so all settings are stable again (unless you have an Asus mobo which has a feature called MemOK, which is why I always go with Asus mobos). Though no need to dive into this here as it's a subject of its own.

As for compability, you could say there are different types of compabilities. What you're referring to is the motherboard's supported RAM speeds - if it's not supported that means you won't even find that speed option in BIOS.
What I'm referring to is compability with the chipset together with the RAM sticks. X99 and Z170 chipsets are known to become incompatible with certain RAM speeds (mostly from 2800MHz to 3000MHz, with 2666MHz and 3200MHz also being unreliable sometimes, but rarely) when you overclock the CPU and/or fill out most RAM slots. This can even take sometime before you get a bluescreen, as everything is fine at first, but then one stick after the other disappears, until all RAM is lost and the system crashes.
More than this, you also have the more uncommon RAM speeds, such as 2600MHz, 2800MHz, 2933MHz, 3466MHz etc, which may be supported by the motherboard, but there's no guarantee that the RAM sticks themselves will work with it - despite edited timings and voltages.

 

[Garrett Tyrna]

No, the RAM frequency the sticks are sold at are just an XMP profile, that won't be used until you've enabled XMP in BIOS - the RAM can run at multiple speeds, both lower and higher, given that you adjust timings and the DRAM voltage accordingly (to a certain limit of course).
This isn't dangerous for the RAM sticks as long as the temperatures are good on both RAM and CPU (which is no problem for DDR4 RAM), or as long as the DRAM voltage is below 1.5V (specified by Intel) as it can otherwise degrade the memory controller on the CPU. Though most people no longer feel comfortable above 1.4V, as it's the highest voltage setting found in XMP profiles.

The only uncomfortable thing is that if you try out a settings that goes unstable right when the computer boots, then BIOS won't boot since it can't find the RAM, and then you need to pick out a battery (called CMOS) from the motherboard to reset everything in BIOS so all settings are stable again (unless you have an Asus mobo which has a feature called MemOK, which is why I always go with Asus mobos). Though no need to dive into this here as it's a subject of its own.

As for compability, you could say there are different types of compabilities. What you're referring to is the motherboard's supported RAM speeds - if it's not supported that means you won't even find that speed option in BIOS.
What I'm referring to is compability with the chipset together with the RAM sticks. X99 and Z170 chipsets are known to become incompatible with certain RAM speeds (mostly from 2800MHz to 3000MHz, with 2666MHz and 3200MHz also being unreliable sometimes, but rarely) when you overclock the CPU and/or fill out most RAM slots. This can even take sometime before you get a bluescreen, as everything is fine at first, but then one stick after the other disappears, until all RAM is lost and the system crashes.
More than this, you also have the more uncommon RAM speeds, such as 2600MHz, 2800MHz, 2933MHz, 3466MHz etc, which may be supported by the motherboard, but there's no guarantee that the RAM sticks themselves will work with it - despite edited timings and voltages.

I really appreciate your time in helping me, this is all very helpful! thank you very much

 

[Jhardware]

I second the appreciation!! Very useful information thanks