ROG Rampage VI Apex Overclocking Guide
The ASUS ROG team prepared an X299 Kaby Lake-X and Skylake-X Rampage VI Apex overclocking guide for those who wish to get the most out of their Core X-series processors. The guide was originally published by Elmor on the HWBOT forums and is shared at Overclocking.guide with explicit permission.
Additional BIOS and tools will be available in the HWBOT forum thread.
Guide Version v1.1
Rampage VI Apex Overclocking: Liquid Nitrogen
Everything is essentially the same as Kaby Lake on Z170/Z270. You can check the Maximus VIII and Maximus IX Apex guides for an update.
Use Slamm’s LN2 profile as a base.
The main difference is that the pin used for DMI voltage is not present anymore, but it’s still mapped to a resistor at the back of the CPU. We’ve solved this by adding a removable pin inside the center of the CPU socket. The pin is included in the motherboard box. It’s suggested to place this pin only on motherboards for LN2 use and tape over the back on Skylake-X CPUs to avoid issues. See Section 8 for installation instructions.
There are four switches available on Rampage VI Apex, which are only usable after LN2 Mode is enabled.
RSVD1 works similar as on M9A, which applies high voltages at startup to ensure you can power on at LN2 temperatures. When the switch is engaged you can’t set lower than the listed voltages, but they can be increased. If you also enable RSVD2, it lets the board know you’re using the DMI pin and will set a more ideal combination of VCCIO and DMI Voltage for lower cold boot and PCI-E cold bug. You should only use RSVD switches on KBL-X.
|Voltage||RSVD1||RSVD1 + RSVD2|
|PLL Bandwidth||Level 8||Level 8|
Overall very similar behavior to Broadwell-E: Cold boot around -80 to -90, cold bug about 10*C colder. Some CPUs have IMC cold bug where you get stuck at AE (sometimes 00 after), need to heat up worst case to -50*C to boot.
Load Extreme LN2 profile as a base
To make sure extreme overclocking rules are engaged:
- Set AI Overclock Tuner to Manual
- Either Vcore or Vcache 1.41V+
Additionally it’s recommended to use the below settings:
- SVID = Disabled
- VCCIO at least 1.35V
- CPU Current Capability = 240%
Typically you want to be at CPU Input Voltage 2.1-2.3V, CPU Core Voltage 1.45-1.6V, CPU Cache Voltage 1.5V-1.6V. Make sure you’re at least at -30*C before applying these settings.
Cache/Mesh frequency scales with Cache Voltage
When applying CPU Ratio under LN2 scenario, it may take over 10 seconds to actually change. You just need to wait after applying. It’s a bug in Intel µCode.
On 0005 BIOS you might have voltages for Kaby Lake-X showing up in BIOS or TurboV Core, such as Core PLL, Standby Voltage, and PLL Termination. Just ignore; changing them does not affect anything on Skylake-X.
Rampage VI Apex Overclocking: DRAM
DRAM Frequency Expectations
|DIMMs per Channel||DIMM Rank||KBL-X Dram Frequency||SKL-X DRAM Frequency|
|Expected||Best Case||Expected||Best Case|
The values are valid with Samsung B-based DIMMs on ambient cooling and HCI Memtest stable, others might not perform as well. DRAM Ratios are functional up to DDR4-4133 on KBL-X and up to DDR4-4400 on SKL-X.
Kaby Lake-X DRAM overclocking
Same as Skylake/Kaby Lake. You might see slightly higher frequency on this board compared to M9A due to board improvements and higher quality IMCs.
New is working DRAM Ratios up to DDR4-4400.
There’s no major difference between 1T/2T command rate in terms of stability and frequency
You want to be at 4000 CL12 1T for best performance
To maximize frequency you can tune Uncore Voltage Offset (+0.2 to +0.6) and Transmitter DQS Pre-emphasis/De-emphasis (1.400-1.600). If using too much you might get stuck at Windows boot logo or get worse POST issues. Typically your sweet spot voltages will be slightly lower on LN2 compared to ambient.
Rampage VI Apex Overclocking: DMI pin
Insert the pin from the back. Make sure it’s all the way in, maybe need to use more force for the last bit.
Use a soldering iron to fix it in place.
After mounting your Kaby Lake-X CPU you need to measure resistance using the ProbeIt pins to check that it has made good contact. Measurement point is the 4th from the bottom, and it should have less than 2K ohm to GND (most CPUs around 40 ohm).
Switching to Skylake-X
If you are switching over to use a SKL-X, there is no need to remove the pin, simply tape up the back of the CPU as shown below.
DMI Pin Removal
To remove the pin, you will want to use a soldering iron or hot air gun from below. When the solder starts to melt, push the pin through from the top. The reason for doing this from below is to make sure that the solder does not flood the hole.
Rampage VI Apex Connectors
USB BIOS Flashback
USB BIOS Flash Back port is the bottom black port (USB2.0) at the back I/O. Filename should be R6A.CAP.
All PCI Express lanes from CPU and X299 PCH are Gen3.
|PCIEX16/X8_1||x16/x8||CPU||Always x16 on SKL-X. x8 on KBL-X if PCIEX16_3 is populated.|
|PCIEX8_2||x8||CPU||Only usable on SKL-X 44-lane CPUs.|
|PCIEX16/X8_3||x16/x8||CPU||Bandwidth depends on PCIEX8_4 for SKL-X. Max x8 on SKL-X 28-lane CPUs. Always x8 on KBL-X.|
|PCIEX8_4||x8/x4||CPU||Only usable on SKL-X.|
|CPU_DIMM.2_1||x4||CPU||Only usable on SKL-X.|
|CPU_DIMM.2_2||x4||CPU||Only usable on SKL-X 44-lane CPUs. Disabled if PCIEX8_4 is configured in x8 mode.|
|PCH_DIMM.2_2||X4||X299 PCH||Supports SATA mode M.2|
|Back top 4x Type-A||USB3_E1234||Blue||USB3.0||X299 PCH||Through ASM1074|
|Back middle 1x Type-A + 1x Type-C||USB3.1_EC1
|Red||USB3.1 Gen2||ASMedia ASM3142||Type-C supports up to 5V 3A|
|Back bottom 4x Type-A||USB1112_U3_56||Black
|X299 PCH||Bottom black/USB2 port is for USB BIOS Flash Back|
|Front USB3.0 header||USB3_12||Grey||USB3.0||X299 PCH|
|Front USB3.0 header||USB3_34||Grey||USB3.0||X299 PCH|
|Front USB3.1 header||USB3.1_EC2||Metallic||USB3.1 gen2||ASMedia ASM3142||Supports up to 5V 3A|
|Front USB2.0 header||USB1314||Grey||USB2.0||X299 PCH|
|Front USB2.0 header||USB10||USB2.0||X299 PCH||Shared with ROG_EXT|
Installing OS from USB
Windows 8+ installs natively
Windows 7 needs USB drivers slipstreamed. Drives can be moved over directly from Z270.
Windows XP is only supported on KBL-X and only on special XOC BIOS builds. X299 currently has problems with Intel XP AHCI drivers, causing IRQL_NOT_LESS_OR_EQUAL BSOD in some cases. Device ID is identical to Z270. It’s recommended to integrate Asmedia ASM106x AHCI drivers in your XP install and use those ports (bottom dark gray). Make sure to disable the Intel SATA controller from BIOS to avoid the BSOD if using this method. Alternatively you can use a PCI-E SATA card with IDE mode support.
|Top 2x + 2x||Light grey||SATA3||X299 PCH||AHCI Mode|
|Bottom 2x||Dark grey||SATA3||ASMedia ASM1061||AHCI Mode|
Rampage VI Apex Overclocking: Known issues
- After BIOS flash reset your bios date/time, crazy values can cause weird issues with certain software
Rampage VI Apex Overclocking: World Records
Intel just announced its latest X299 platform and accompanying series of high-end-desktop processors. Using the new Rampage VI Apex motherboard, the ROG Overclocking team broke a total of seven world records and captured 16 global first places on the Core i7-7740X, i7-7800X, i7-7820X and i9-7900X. They also hit the highest CPU frequency for a Intel Core i7 processor with 7.562GHz on all four cores and eight threads. Doing so required exotic cooling methods, including liquid nitrogen (LN2) and even liquid helium. (June 2nd, 2017 – ROG Blog entry)