• This email address is being protected from spambots. You need JavaScript enabled to view it.
Overclocking Guide for DDR4 RAM banner

User Rating: 5 / 5

Star ActiveStar ActiveStar ActiveStar ActiveStar Active

Article Index


Starting to overclock by simply booting into your BIOS and look for the DRAM, VCCIO, VCSSA and SoC(AMD) voltages. Make sure no XMP profile is selected and set the RAM profile manual. Also, check if MRC Fast Boot is turned off in the Timings section of your BIOS can be found in some high-end motherboard. Example BIOS from an ASUS Maximus Hero XI.

Default Memory profile

To start overclocking your DRAM you want to adjust your DRAM voltage to 1.45v, Intel VCCIO and VCCSA voltages to 1.15v or AMD SoC voltage to 1.10v.

BIOS voltages for Intel

Leaving all the timings to Auto you just want to increase the memory frequency with the voltages entered and see how fast your RAM kit can run. Depending on your XMP profile you want to start higher so with a 3200mhz XMP kit you want to start with 3600Mhz. If your RAM kit XMP profile is rated higher you want to start 400Mhz higher then the base XMP profile. Make sure all the timings are set to Auto, that includes the Primary Timings, Secondary Timings etc. Just want to get the highest possible memory frequency and then work on the timings. With AMD Ryzen you want to set the FCLK half of your memory speed, so when using for example 3600mhz then set the FCLK to 1800mhz.

Frequencies selection tab

After selecting a frequency then save these settings in the BIOS and reboot. Your PC might reboot a couple of times adjusting the timings since you changed the frequency. If your RAM kit can run the speed it will boot right into Windows. If it fails it will show a failure to post a message. In the case of a failure, you can increase VCCIO and VCCSA voltages for Intel from 1.15v to 1.2v or 1.25v and for AMD the SoC voltage from 1.10v to 1.20v or 1.25v. Or dial back the memory frequency 1 step from the previously selected memory frequency while keeping the same voltages. When it does boot into windows use Aida64 Cache & Memory Benchmark or MaxxMEM2 to gauge if your overclock is stable checking the Read, Write, Copy and Latency. For Intel, you want a Latency between 55ns and 60ns without changing the timings and for AMD timings between 75ns to 80ns. And always an increase in Read/Write/Copy speeds. The first indication of instability is the memory having to correct for errors that will lower Read/Write/Copy speeds. You might also be able to boot into Windows but when running a benchmark your PC could shutdown or BSOD that also is an unstable memory overclock. When using a Ryzen CPU make sure you keep adjusting your FCLK to half the memory frequency.

Aida64 benchmark performance gain example

Repeat this process to get the highest possible frequency on your RAM kit. Stop increasing the frequency as soon as it fails to boot into Windows or when you see a decrease in Read/Write/Copy speeds. Then you want to increase the VCCIO and VCCSA voltages for Intel from 1.15v to 1.2v or 1.25v and AMD the SoC voltage from 1.10v to 1.20v or 1.25v if you have not done so already. Also, something to look for the timings that are automatically set by your PC and make sure that those do not get overly loose. When you get a high frequency but your timings are so loose in the range of 25-25-25-50 or more you might want to consider running a lower frequency. With higher VCCIO, VCCSA or AMD SoC voltages you can try to keep the frequency that failed to post or did not return a better benchmark. But in general DRAM voltage gives a bigger boost and VCCIO, VCCSA and SoC help to stabilize overclocks that boot bu won't pass a stress test.

When you have established the highest possible memory frequency it is time to tighten the timing. Here you start with the Primary Timings. To consider is that the best RAM kits run timings of 14-14-14-32 @ 3200mhz or 16-16-16-38 @ 3600mhz with 1.35v. This gives you a good indication with whatever max memory frequency you have for what memory timings you want to aim for and what is possible. Make sure the Command Rate is set to CR1/T1/N1 unless you are using a memory kit of 4 sticks then use CR2/T2/N2. If your timings on Auto went to CR2 regardless of the number of sticks keep these settings since using CR2 is slightly less demanding to overclock. You can consider using CR1/T1/N1 but expect less Mhz and looser timings only really well binned ICs do well on CR1. And you can consider a wider range of overclocked profiles and pick your daily driver from there but it will take considerable more time testing and stress testing each profile for 100% stability.

Some important notes on adjusting the timings you want to make sure the 1st timing is only 1 or 2 steps away from the 2nd and 3rd timings. Only B-Die can run the same timings on the first 3 timings, for example, 16-16-16 for the first set. Other IC's you want to keep the first timings as low as possible but only loosen the 2nd and 3rd timing, as an example 16-18-18 for the first set. The 4th timing you want to double of the 3rd timing and if needed to be looser + 4 steps. As example 14-14-14-32, 19-19-19-38 and 17-19-19-38. Below are some more primary timings to consider as an example.

Example B-die Timings.

  • 14-14-14-32
  • 15-15-15-34
  • 17-17-17-34
  • 19-19-19-38

Example RAM Timings.

  • 14-15-15-32
  • 14-16-16-32
  • 16-18-18-36
  • 17-19-19-38

UEFI BIOS primary timings

You want to keep making the timings tighter until the PC fails to boot or you start seeing a drop in Read/Write/Copy speeds in Aida64 or MaxxMen2. Adjusting Primary Timings will also lower the latency so you should also see a drop in latency. The latency of about 45ns is good but you can get the latency to drop below 40ns. In short, you want the Primary Timings as tight as you possibly can. You want to make sure that these timings are stable you can run a demanding benchmark like Fire Strike Ultra in 3DMark. And do a 2 hours custom 512FFT to 4096FFT stress test before working on Secondary and Tertiary Timings.

The final timings you want to adjust are tREFI and tRFC these works best if adjust as a pair be can be done separately. The tRFC timing you want to lower as much as you can a tRFC of 300 or lower is very good but this will also depend on the motherboard and RAM kit quality. Starting with a tRFC of 450 is a save starting point and work the tRFC down as low as you can. tREFI is the opposite of all timings and you want this value as high as you possibly can, some overclocks have a tREFI of 65000 or higher but those are on the high-end motherboards like the Maximus Hero XI Extreme. And an easy tREFI to have stable is 25000. Adjusting tRFC and tREFI just like the Primary Timings by adjusting them until Windows fails to boot and/or the Aida64 or MaxxMem2 benchmarks show a drop in Latency but not an increase in Read/Write/Copy speeds.

UEFI BIOS secondary timings

DDR RAM Overclocking Banner

DDR RAM Overclocking Terminology FAQ

DDR RAM Overclocking Terminology FAQ This Terminology FAQ covers overclocking for DDR RAM for both Intel and AMD platform and adds a reference material for various guides found on hisevilness.com. RAM
Overclocking Guide for DDR4 RAM banner

Overclocking Guide for DDR4 RAM

This easy comprehensive guide illustrated with images is for the overclocking DDR4 using several brands such as Corsair and G.Skill with different IC's as an example. This guide is to supplement
Intel overclocking intro

Intel Overclocking Terminology FAQ

Intel Overclocking Terminology FAQ. The Basics. This FAQ will answer the most common questions when overclocking Intel CPUs. This will cover Intel-based CPU's over about a decade. For the most part,
© 2016 -2019 Paul "HisEvilness" Ripmeester. All Rights Reserved.