Overclock i5-8600k with some benchmarks

[samuel9521]

Hi All,
I have an intel core i5-8600k overclocked to 5GHz at 1.33V, but I tested it at 1.39V @5.1GHz, and it seems to be stable.
Do you think it's safe to set this voltage for everyday usage?
Thanks in advance

[Silent_Scone]

samuel9521 wrote:
Hi All,
I have an intel core i5-8600k overclocked to 5GHz at 1.33V, but I tested it at 1.39V @5.1GHz, and it seems to be stable.
Do you think it's safe to set this voltage for everyday usage?
Thanks in advance

Yes, up to 1.4v is fine on that CPU. Just be sure to try and keep temps under 80C. For the jump in voltage required, it's arguably not worth it.

[samuel9521]

Ok I tried lowering the voltage below 1.39V @5.1GHz, but it's unstable.
With that voltage, I managed to set the max cache ratio at 45, and the system passed aida64 stress test and various benchmarks, like Geekbench 4, Cinebench R15 and CPU-Z with a maximum temperature of 72°. I also set the CPU current capability to 120%, while drams are running @3866MHz at 1.4V with VCCIO at 1.1875V, VCCSA at 1.2125V and 15-15-15-36 timings.

Here are some results if you want to compare:

Cinebench R15: 223cb single-core, 1285cb multi-core

Geekbench 4: 6608 single-core, 26082 multi-core

CPU-Z: 617.2 single-core, 3618.3 multi-core

Aida64: 62585 CPU Queen, 8330MB/s CPU Hash, 31555MPx/s CPU PhotoWorxx, 975.9GFloPS Single-Precision, 486.8GFloPS Double-Precision

[Bronson]

Hi Samuel9521, can you tell me the settings in the bios you use?
i am having trouble getting my i5 8600k over 5ghz, runnign at the mom 4.9ghz at 1.4 volt. anything lower boots but my games keep crashing.

[samuel9521]

Actually I had some random crashes at 5.1GHz, so I went down to 5.

Note that my settings may not work with your system, exceptionally for DRAM settings.

My current settings are:

AI Overclock Tuner	Manual
BCLK Frequency	100.0000
ASUS MultiCore Enhancement	Disabled
SVID Behavior	Auto
AVX	0
CPU Core Ratio	Sync All Cores
-1 to 6-Core Ratio Limit	50
BCLK Frequency : DRAM Frequency Ratio	Auto
DRAM Odd Ratio Mode	Enabled
DRAM Frequency	DDR4-3866MHz
TPU	Keep Current Settings
Power-saving & Performance Mode	Performance mode
CPU SVID Support	Disabled
CPU Core/Cache Current Limit Max	255.50
CPU Graphics Current Limit	255.50
Ring Down Bin	Auto
Min CPU Cache Ratio	Auto
Max CPU Cache Ratio	45
Max CPU Graphics Ratio	25
BCLK Aware Adaptive Voltage	Auto
CPU Core/Cache Voltage	Manual Mode
-CPU Core Voltage Override	1.345
DRAM Voltage	1.4058
CPU VCCIO Voltage	1.0875
CPU System Agent Voltage	1.1375
CPU Graphics Voltage	Offset Mode
-CPU Graphics Voltage Offset	0.150
PCH Core Voltage	1.00000
CPU Standby Voltage	Auto
DRAM TIMING CONTROL
DRAM CAS# Latency	15
DRAM RAS# to CAS# Delay	15
DRAM RAS# ACT Time	36
INTERNAL CPU POWER MANAGEMENT
Intel SpeedStep	Disabled
Turbo Mode	Enabled
Long Duration Package Power Limit	4095
Package Power Time Window	127
Short Duration Package Power Limit	4095
TWEAKER'S PARADISE
FCLK Frequency	1GHz
ADVANCED\CPU CONFIGURATION\CPU - POWER MANAGEMENT CONTROL
Intel SpeedStep	Disabled
Turbo Mode	Enabled
CPU C-states	Disabled
CFG Lock	Disabled
Intel Speed Shift Technology	Disabled

[Bronson]

Ok, thanks for the info, i tried them but still no luck on getting 5ghz stable.
I currently use your settings with 4.9ghz @ 1,36volt with max temps at 70C.
i also tried different digi+ vrm settings
cpu llc - lv5
cpu current capacity - 140%
vrm switching frequenzy - manual , at 500

I hope to break that 5ghz barrier on my i5 8600k. if you have any ideas, i plan on deliding it but not now.

[av3nger]

Stable clocks at 5ghz can get tricky with i5. The motherboard can play a huge factor. What motherboard are you running?

[Bronson]

Hello av3nger,

i am using the Asus ROG Z370 F.
My CPU cooler is the Be Quiet! Dark Rock Pro 3.
you can see al my specs under my name.
at the moment i am just happy if can get my earlier 4.9ghz stabel again 😞
i have been playing around so much that its not stabel anymore.

[Bronson]

Hi,
long time no see 😄
with the new bios 1406, i got it stabel at 4.9 ghz with your settings (except the ram). i should get higher settings on my ram since the sticks are rated higher then my current 3200mhz, hmm maybe i should try loosening the timings a little.
also i was just looking into BCLK overclocking, it seems to give a little more performance.

[samuel9521]

Hi Bronson, nice to see that you didn't give up 😄

Here I attached screenshots of my stable bios settings for 5GHz. I think you should try to overclock your system in an ordered way as I did (the bios offers you a way to save your settings in the Tool menu):
1) set all the values from Auto to their default ones (for example 43 in CPU Core Ratio and 2133 for RAM frequency), and set all the power settings as in my screenshots;
2) overclock your RAM by changing frequency, timings and voltage;
3) overclock your CPU just by changing ratio and voltage (you will have set all the power and llc settings in digi+ vrm page at step 1);
4) overclock FCLK and Cache.

With your RAM, you should use their factory overclocked speed (mine is 3866), set both VCCIO and VCC System Agent to 1,25, and then you could try lowering the timings together with the voltages (if your sticks are good, you should be able to reach 1,5 V but i don't think it's worth, and in some cases VCCIO and VCCSA can get quite low - i set them to 1,075 and 1,125).
Before changing the timings, try using 1N as the DRAM Command Rate, and if it fails booting up or if it's unstable, just set it to 2N.

In order to test RAM stability, I recommend you this software: http://virgilioborges.com.br/hyperpi/
Run the test on all cores with 32M digits, it will take 7 to 11 mins to complete. If an error occurs, it means that your overclock is unstable.

During your tests, run a 10 mins stress test in Aida64 and see if it's all good (temperatures too, with my settings I get an average of 69°C with a CM MasterLiquid Pro 240).
Try also doing multiple benchmarks with softwares like Cinebench, Geekbench, CPU-Z, etc.

I don't know pretty much anything about BCLK overclock, I tried it some times but I failed, and I don't actually think it's worth doing it with a mainstream CPU, maybe it could be nice on a server machine.