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REVISED Overclock BIOS Settings for i7-8086K on Asus ROG Maximus X Hero WiFi AC

Level 7
Overclock BIOS settings for i7-8086K on Asus ROG Maximus X Hero (WiFi AC) [BIOS v1801]

Note 1: Manual OC settings only. Does not include Adaptive/Offset Voltage settings or how to acquire them.
Note 2: Cleaned up document and included updated lowered BIOS Vcore= of 1.290v from 1.330v

BIOS settings (details below):
5.2GHz: Vcore=1.29v, 52x CPU Core Ratio Limit, AVX offset= -2, 49x uncore, LLC=6
5.0GHz: Vcore=1.30v, 50x CPU Core Ratio Limit, AVX offset= -2, 46x uncore, LLC=6



Note: BIOS upgrades wipe out all saved profiles, save notes on settings used.

CPU Cooler: Corsair H100i Pro RGB dual 120mm Fans with PWM control AIO cooler. If running air cooling temps will be a bit higher.

CPU: I7-8086K delidded with Rockit Cool Copper Upgrade Kit for 1151 incl. delid/relid tools and Copper IHS (Integrated Heat Spreader). Used Thermal Grizzly Conductonaut Liquid Metal between CPU and Copper IHS and between Copper IHS/CPU and Corsair H100i Pro heatsink.

Note: Only need to have liquid metal barely on the surface. Don't leave 'puddles' or 'drops'. Liquid Metal is electrically conductive and will short out components if too much is applied and excess squeezes out or dropped. Thermal "Grease" (Such as Thermal Grizzly Kryonaut 12.5W/mK thermal conductivity) is NOT electrically conductive so much safer but not as efficient as liquid metal (Thermal Grizzly Conductonaut 73W/mK thermal conductivity). Do not overuse or it may 'squeeze out' of CPU Heatsink to short out motherboard components or CPU SMD's. Use clear nail polish on SMD devices on CPU after delid and allow to dry to protect devices. Go easy w/ liquid metal on CPU/CPU Cooler. Use rubbing alcohol on cloth to remove spills. Lightly squeeze to "pickup" the drop(s) with the alcohol cloth. Wiping only spreads it around for more mess.

ESD (Electrostatic Discharge): Contrary to what is seen on many 'tech' YouTube video's, ESD is real and can damage components. Component damage can cause immediate failure/error or intermittent failure making it extremely difficult to pinpoint the bad component. I've seen 20%+ return rates on expensive new motherboards installed on new (and some repaired) PC's because techs did not protect against ESD. They would pick up CPUs, RAM, m/b's, graphics & other cards touching the electrical contacts on the edge of the card thinking there was nothing wrong and would even say they don't have an ESD problem (themselves). Everyone generates ESD. You don't have to see or hear a 'spark' or feel it to cause damage. Always wear an ESD wrist strap connected to an unpainted part of the case or other ground. The strap should have a resistor (1-10 MegOhm) to protect against electrocution in case of contact with live power. The resistor will be destroyed to open circuit & disconnect you from live current. Intel used to test all RMA'd motherboards for ESD or other damage. Don't know if anyone still does. ESD is real despite the 'heroics' you see on YouTube. No one is automagically protected or immune from ESD. The techs are not, and neither are the components. The laws of physics do not change. Our components are shipped in anti-static bags and have ESD warnings on them for a reason.

BIOS OC Optimization Notes:

- CPU Temp Max is approx 90C. Prefer closer to 70-75C or lower under max load during stability testing. Stay away from 95C.

- CPU Core Voltage Max is approx 1.40 volts (i7-8700K, I7-8086K). Prefer 1.40v or lower under max load during stability testing.

- Never use XMP settings to OC CPU. These set CPU voltages way to high by default. XMP can be used to ascertain RAM settings which can then be set manually, and XMP disabled after.

- YouTube video on Load Line Calibration indicated it should never be set higher than 3, or maybe 4. Anything higher can damage the CPU. Check to see if LLC >=6 helps as 2 different OC'ers indicate. Changed from 3 to 6 and found that voltage went up from about 1.28v to 1.32v immediately. Vdroop issue required LLC=6 after testing with 3,4,5. Problem was that even though Vcore was set manually, actual Vcore went quite a bit lower causing issues. LLC was limiting current/voltage to the CPU. LLC allows increased current flow to eliminate Vdroop issues causing instability. After setting LLC=6, HWMon shows Vcore that is slightly higher than what was set in the BIOS but no more issues due to Vdroop under load.

- Rainmeter desktop monitor app interferes with proper operation of CPU-Z (any version) Hardware Monitor etc. Tested using Windows Gadgets (CPU and Network Meter). No issues.

- set uncore @ 49 (5.2Ghz) and 46 (5.0Ghz) but can go as low as 40 w/o big performance loss. Uncore is ring bus, northbridge or cache ratio and is the cache speed on the CPU. Only OC the uncore once you get solid stability on OC. Uncore should never be faster than Core clock and only helps about 1/14th as much as core OC. Can increase uncore after stable CPU OC is achieved.

- FCLK Freq for early power on from auto to 1Ghz

The following is not strictly related to Overclocking:

- Set CSM to manual then set all items for UEFI first, then set CSM back to Auto. If CSM is on auto, get much sharper (and smaller) text on POST with Asus ROG Logo. May need to change settings if using storage that requires Legacy MBR instead of UEFI GPT boot settings.

OC Stability Test:
- Get Core Temp v1.7 or later to test core temps or use CPUID HW Monitor.

Stability Testing Apps:
1 - Intel Burn Test v2.54 for 10 loops. More accurate than Prime95, 8 minutes using Linpack to test vs 40 hrs under Prime95, same test Intel uses before shipping CPU. Run at standard then run at Maximum to use all RAM. Very High is best balance and doesn't take as long as Max does. Intel Burn Test v2 uses some AVX instructions and thus lowers CPU core ratio by 2 (due to BIOS AVX Offset = -2) for core ratio of 50 instead of 52. CPU runs @ 5.0Ghz instead of 5.2Ghz under AVX loads. Can set AVX Offset to -2 to start and raise to -1 or 0 and test to get max uncore performance. May need to lower to -3 or more if required under load/stability testing.
2 - Cinebench
3 - RealBench
4 - AIDA64 Extreme (paid, can try free), Tools, System Stability Test. Shows temps and if CPU throttles or not in the graph. Best util to test RAM with via Cache and Memory Benchmark
5 - Prime95: Run Custom: 12 threads (one for each logical core, 12x for 8700k/8086k, Min/Max FFT Size=1344, Enable Run FFT's in place, Time to run each FFT (min)=15 and run for 1 hr or more.
6 - GeekBench (free). Sign up for a free account but will auto post your results to your account under your profile.


Setup all fan profiles and save them in BIOS > Tool > ASUS Coverclocking Profile > Profile Setting > Profile Name (e.g. FanProSet) > Save to Profile (enter # for profile slot to save to e.g. 1 to save to Profile 1 Status). This allows you to have your fan profile settings automatically as part of all your new test profile(s)

Used ASUS AISuite 3 Windows Utility which was running fan speeds well and noted settings and basically used these settings for BIOS so as to avoid having to run fan control from Windows.

Can also use Asus AI Suite 3 to change some BIOS settings from within Windows. Settings here are changed in the UEFI BIOS instead of Windows.

Go to BIOS > Monitor and note Fans which have active RPM's as these are the fans you will configure. The following fan power connectors were used in this case:
Chassis Fan 1
Chassis Fan 2
Chassis Fan 3
AIO Pump
CPU Optional Fan

No installed extension cards for fans and Flow Rate is N/A.

Can try to use the BIOS fan profiles (Standard, Silent, or Turbo) for all " XXXXX Fan Profile" settings below. Turbo causes Fans to run at full speed max fan noise. Use TURBO to get a temperature baseline during Stability Testing. Can then change to Standard or Silent and test again. Settings below do cause some fan noise, but not as much as Turbo. Below does allow fans to speed up to full speed when CPU temps go high during high CPU load in Windows.

BIOS > Monitor > Q-Fan Configuration > Q-Fan Tuning

Note: Using Corsair H100i Pro RGB AIO water cooler which requires connection to the CPU fan header.

CPU Q-Fan Control - Auto (Set to AUTO to autodetect DC 4-pin connector or PWM 3-pin connector. PWM fans allow better speed control)
CPU Fan Step Up - 0 sec
CPU Fan Step Down - 0 sec
CPU Fan Speed Lower Limit - 200 RPM
CPU Fan Profile - Manual
CPU Upper Temperature - 45
CPU Fan Max. Duty Cycle (%) - 100
CPU Middle Temperature - 35
CPU Fan Middle. Duty Cycle (%) - 70
CPU Fan Lower Temperature - 25
CPU Fan Min. Duty Cycle (%) - 60

Chassis Fan(s) Configuration:

Chassis Fan 1 Q-Fan Control - Auto
Chassis Fan 1 Q-Fan Source - CPU (so that FAN speed will be based on CPU temp since not using Thermistor cable to monitor another device)
Chassis Fan 1 Step Up - 0 sec
Chassis Fan 1 Step Down - 0 sec
Chassis Fan 1 Speed Low Limit - 200 RPM
Chassis Fan 1 Profile - Manual
Chassis Fan 1 Upper Temperature - 45
Chassis Fan Max. Duty Cycle (%) - 100
Chassis Fan 1 Middle Temperature - 35
Chassis Fan 1 Middle. Duty Cycle (%) - 70
Chassis Fan 1 Lower Temperature - 25
Chassis Fan 1 Min. Duty Cycle (%) - 60

Chassis Fan 2 Q-Fan Control - Auto
Chassis Fan 2 Q-Fan Source - CPU
Chassis Fan 2 Step Up - 0 sec
Chassis Fan 2 Step Down - 0 sec
Chassis Fan 2 Speed Low Limit - 200 RPM
Chassis Fan 2 Profile - Manual
Chassis Fan 2 Upper Temperature - 45
Chassis Fan 2 Max. Duty Cycle (%) - 100
Chassis Fan 2 Middle Temperature - 35
Chassis Fan 2 Middle. Duty Cycle (%) - 70
Chassis Fan Lower Temperature - 25
Chassis Fan Min. Duty Cycle (%) - 60

Chassis Fan 3 Q-Fan Control - Auto
Chassis Fan 3 Q-Fan Source - CPU
Chassis Fan 3 Step Up - 0 sec
Chassis Fan 3 Step Down - 0 sec
Chassis Fan 3 Speed Low Limit - 200 RPM
Chassis Fan 3 Profile - Manual
Chassis Fan 3 Upper Temperature - 45
Chassis Fan 3 Max. Duty Cycle (%) - 100
Chassis Fan 3 Middle Temperature - 35
Chassis Fan 3 Lower Temperature - 25
Chassis Fan 3 Min. Duty Cycle (%) - 20

HAMP Fan Control - Auto
HAMP Fan Source - CPU
HAMP Fan Step Up - 0 sec
HAMP Fan Step Down - 0 sec
HAMP Fan Speed Low Limit - 200 RPM
HAMP Fan Profile - Manual (Try Standard or Silent if too noisy but test to be sure CPU temps are ok.)
HAMP Fan Upper Temperature - 45
HAMP Fan Max. Duty Cycle (%) - 100
HAMP Fan Middle Temperature - 35
HAMP Fan Middle. Duty Cycle (%) - 35
HAMP fan Lower Temperature - 25
HAMP Fan Min. Duty Cycle (%) - 20

AIO_PUMP/W_PUMP+ Control - Auto
AIO_PUMP/W_PUMP+ Upper Temperature - 45
AIO_PUMP/W_PUMP+ Max. Duty Cycle (%) - 100
AIO_PUMP/W_PUMP+ Middle Temperature - 35
AIO_PUMP/W_PUMP+ Middle Duty Cycle (%) 100
AIO_PUMP/W_PUMP+ Lower Temperature - 25
AIO_PUMP/W_PUMP+ Min. Duty Cycle (%) - 100

> Extreme Tweaker

AI Overclock Tuner – Manual (Set to XMP to see what your RAM can be set at, then set back to manual)

BCLK Frequency – 100 (for K-series CPU's to enhance stability)

Asus Multicore enhancement – Disabled (Setting these manually)

SVID behavior – Best Case Scenario (was: Typical Scenario. Should not matter if not using offset/adaptive voltage, but rec'd a blue screen during boot right after changing it to Typical from Best Case. Leaving at Best Case)

AVX Instruction Core Ratio Negative Offset – 2 (AVX instructions cause higher CPU load. This lowers Core ratio under AVX load to avoid issues so 52x Core ratio would be lowered by -2 to 50x core ratior under AVX loads.)

CPU Core Ratio – Sync All Cores

1 – Core Ratio Limit (Start at 48 for 8700K, 50, 51, 52, for 8086K & Test)

BCLK Frequency: DRAM Freq Ratio – Auto or 100:100

DRAM Odd Ratio Mode – Enabled

DRAM Freq – Use settings for your RAM. OC RAM after stable CPU OC.

Extreme Tweaking - Disabled

TPU – Keep Current Settings

CPU SVID Support – Disabled (to allow full manual CPU voltage control instead of mfr 'table' of settings)

DRAM Timing Control – Memory Presets: Auto (set to match your own RAM specs)

>External Digi+ Power Control

CPU Load-Line Calibration – Level 6 (avoids Vdroop issues)

CPU Current Capability – 140%

CPU VRM Switching Freq – Manual (can use Automatic)

Fixed CPU VRM Switching Frequency (kHz) – 400 (or use Auto. Mfr max setting of 500 for your motherboard will cause extra heat)

VRM Spread Spectrum - Auto

CPU Power Duty Control – TProbe

CPU Power Phase Control – Standard

CPU VRM Thermal Control – Auto

DRAM Current Capability – 130%

DRAM Switching Frequency - Auto

Boot Voltages: Set all to Auto

> Internal CPU Power Management

Intel (R) SpeedStep – Disabled

Turbo Mode – Enabled

Long Duration Package Power Limit – 4095 (This is max. setting. To avoid throttling under max power load)

Package Power Time Window – 127 (which is maximum)

Short Duration Package Power Limit – 4095 (This is max. setting. To avoid throttling under max power load)

IA AC Load Line – Auto (when using manual voltage)

IA DC Load Line - Auto (when using manual voltage)

TVB Voltage Optimizations - Auto

> Tweakers Paradise (should be ok to leave alone except for setting FCLK Frequency for Early Power On - 1Ghz (For faster boot up)

CPU Core/Cache Current Limit Max – 255.75

Ring Down Bin – Auto

Min CPU Cache Ratio – 46 (set this to 300-500 Mhz less than Core ratio. 46 Ok for 50 core ratio for 5 GHz, 49 works for 5.2Ghz)

Max CPU Cache Ratio – 46 (set this to 300-500 Mhz less than Core ratio. 46 Ok for 50 core ratio for 5 GHz, 49 works for 5.2Ghz)

CPU Core/Cache Voltage – Manual Mode

- Core Voltage Override – 1.290 (for 5.2Ghz) and move up slowly if required.

BCLK Aware Adaptive Voltage – Disabled (to allow full CPU voltage control.)

DRAM Voltage – Auto (check mfr RAM voltage. If unstable, check VCCIO 1.15v to 1.3v max)

CPU VCCIO Voltage – Auto (can lower after low CPU voltage confirmed as stable)

CPU System Agent Voltage – Auto (can lower after low CPU voltage confirmed as stable)

PLL Termination Voltage - Auto

PCH Core Voltage – Auto

CPU Standby Voltage – Auto

>DRAM REF Voltage Control - All these should be Auto

> CPU Configuration

Hyper-Threading – Enabled

Thermal Monitor – Enabled

Active Processor Cores – All

Hardware Prefetcher – Enabled

Adjacent Cache Line Prefetch – Enabled

Boot Performance Mode – Auto ( using Turbo Performance)

Tcc offset Time Windows – Auto

> CPU Power Management Control

Intel SpeedStep ™ - Disabled

Turbo Mode – Enabled

CPU C-States – Disabled

CFG Lock – Disabled: CFG Lock prevents OS X from writing to a certain region in your BIOS. OS X does this for power management and other reasons, and if it can't access it, it will not boot. VT-d causes kernel panics related to the AppleACPIPlatform kext, which dropped support for VT-d a long time ago. Only enable CFG LOCK if installing macOS

Intel® SpeedShift Technology – Disabled

> Advanced

Execute Disable Bit – Enabled

> Advanced
> PCH Storage Configuration
Aggressive LPM Support - disable to avoid loss of mechanical HD performance and possible early hard drive failure if you have mechanical hard drives installed.

Save changes and Reset

Delidding usually gains 15-25deg C of headroom so that if CPU was maxed during testing at 4.8Ghz @ 89degC it should run 4.8Ghz @ about 70-75degC or lower.

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The Complete 8700K/8086K Delidding Guide by Boosted Media

The Kaby Lake Overclocking Guide

Gigabyte Z370 Guide to Overclocking Coffee Lake CPUs to 5Ghz+

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Thermal Grizzly

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