Time for another run at some overclocking, today I'm finally going to squeeze the juice out of my Core i5-4670K.
My "little engine that could" OC system:
- Intel Core i5-4670K (3.4 GHz, 1.5 V --- Boost: 3.8 GHz, 1.15 V)
- Asus Maximus VII Impact (BIOS 3003)
- Noctua NH-L12 with two fan setup
- Crucial Ballistix Sport VLP 2x 8GB PC3-12800 (9-9-9-24)
- Samsung 960 EVO 256GB
- In Win Chopin with the sidepanel removed
- Fans set at "performance mode"
- Windows 10 x64 - basic install (including all drivers)
- AIDA64 for checking basic stability/temps/volts
Some basic settings I've made to start:
- CPU Ratio - All Core (so all cores get the same ratio)
- BCLK - 100.0
- Intel SpeedStep - Disabled
- Intel TurboBoost - Disabled
- Asus MultiCore Enhancement - Disabled
- RAM - XMP Profile 1 (DDR3-1600 9-9-9-24 1.35V)
- Cache min ratio: 35
- Cache max ratio: 35
First step: Probing.
Temps are average CPU after 15 minutes of AIDA stability test. I'll be trying to maximize the clock from the default 1.15 V up to 1.45 V, with the expectation to be running 1.3 V or lower long-term. The first part was done using only the 92mm fan on the heatsink.
Fixed CPU voltage at 1.15 V with 1.85 V input voltage (default)
- 38 x 100 at 1.15 V --- ~70°C (default clocks)
- 40 x 100 at 1.15 V --- ~75°C (4.0 GHz)
- 42 x 100 at 1.15 V --- ~78°C (66°C package temp)
- 44 x 100 at 1.15 V --- ~80°C (68°C package temp)
- 46 x 100 at 1.15 V --- FAIL after 10 minutes
Fixed CPU voltage at 1.20 V with 1.85 V input voltage
- 46 x 100 at 1.20 V --- ~90°C (77°C package temp)
- 48 x 100 at 1.20 V --- FAIL at login
Fixed CPU voltage at 1.25 V with 1.85 V input voltage, adding 120mm fan to heatsink for dual-fan configuration
- 48 x 100 at 1.25 V --- ~85°C (72°C package temp)
- 50 x 100 at 1.25 V --- FAIL during boot
Fixed CPU voltage at 1.25 V with 1.90 V input voltage
- 50 x 100 at 1.25 V --- FAIL during boot
Fixed CPU voltage at 1.30 V with 1.90 V input voltage
- 50 x 100 at 1.30 V --- FAIL during boot
Here I decided to increase the CPU voltage to 1.35 V input voltage to 2.00 V, but also set the cache voltage to 1.25 V, System Agent voltage to 1.25 V and disable SVID Support.
- 50 x 100 at 1.35 V --- FAIL at login
- 50 x 100 at 1.375 V --- FAIL at login
- 50 x 100 at 1.40 V --- FAIL at login
Fixed CPU voltage at 1.40 V with 2.10 V input voltage
- 50 x 100 at 1.40 V --- FAIL at start of AIDA stress test
- 50 x 100 at 1.43 V --- FAIL at start of AIDA stress test
- 50 x 100 at 1.45 V --- FAIL at start of AIDA stress test
It's clear I'm hitting a ceiling here, either the CPU goes into thermal shutdown or I'm htting some other limit. Nonetheless I was able to boot into Windows, take a CPUID screenshot and do a submission to HWBOT.org. But clearly I should start finetuning with the CPU multiplier at 48, since I'm not planning to run continuously at 1.40 V or higher anyway and am not planning to use a beefier cooler.
