i5 6600k overclocking temps
i5 6600k overclocking temps
I attempted it right now with speed step active and balanced control plan, but my voltage doesn't decrease—it only the frequency drops.
As soon as I applied my adaptive voltage settings, the voltage reduced while the frequency decreased.
VanWassa adjusted the i5 6600K overclocking settings. Initially set at 4.3 with auto voltage stability, it was changed to 4.6 GHz with auto voltage enabled (resulting in a voltage of 1.328 V). During testing, the temperatures reached up to 78°C during the AIDA 64 Full Stability Test for 10 minutes. Idle temperatures stayed around 30°C. When playing The Witcher 3 at 1440p with Hairworks off, temperatures were approximately 65–70°C maximum, and around 74°C during play. For GTA 5 (reduced resolution), temperatures hovered between 65–75°C, averaging about 80°C. Overall, the temperatures are manageable but slightly elevated. The current cooling solution is adequate, though upgrading to a better fan or improving airflow could help lower the readings further. The PC specifications include an i5 6600K CPU, ARCTIC Liquid Freezer cooler, 16GB RAM, and a Palit Jetstream GTX 1070 GPU. The PSU is Be Quiet System Power 8 at 600W, and the motherboard is ASUS Z170-K.
VanWassa shared that speedstep didn't improve performance; it remained at 1.280 even with the lowest setting. He also faced voltage drops when speedstep and c-states were enabled, specifically on a gigabyte board. He plans to post elsewhere to avoid cluttering this thread.
VanWassa shared their experience: speedstep didn't improve things; it kept the core at 1.280 even with lowest settings. They're facing similar problems when their voltage decreases while using speedstep and c-states, especially on a gigabyte board. They plan to post separately to avoid cluttering this thread.
Regarding temperatures, they previously maintained stable performance at 1.290Vcore (CPU-Z: 1.284) with XMP Profile 1 enabled on Corsair Vengeance DDR4 3000MHz. After three hours of OCCT LINPACK and CPU large tests, temperatures rose above 80°C during OCCT CPU Small runs. Using the "Relax OC" memory enhancement lowered their temps by about 10 degrees and allowed them to pass all benchmarks. They're unsure what "Relax OC" does but note that BIOS still reports identical DRAM voltages and timings when it's active.
Their system specs include:
- Motherboard: Gigabyte Z170 Gaming 3
- CPU: i5 6600k
- CPU cooler: EVO 212
- RAM: 16GB Corsair Vengeance DDR4 3000MHz
- GPU: Gigabyte GTX960OC 2GB
They mentioned the thread is fine as it is, since overclocking at 6600K affects temperatures too.
For voltage and idle performance, they recommend enabling Speedstep (it's default) and setting the Windows Power Plan to "Balanced." The Performance plan disables Speedstep unnecessarily, keeping everything at maximum which wastes resources. They suggest leaving the Memory Enhancement at "Normal" to keep timings accurate.
They also advise using the CPU EIST function for better idle cooling and adjusting CPU Enhanced Halt (C1E) and C3/C7 support accordingly.
Grimsin explains that adjusting the settings generally increases the frequency from 3000mhz to 16-17-17-40, which slightly reduces speed but still maintains performance within that range. It notes it's not straightforward to know the exact impact of "Relax OC," as your personal configurations remain intact. The term "bandwidth" likely refers to frequency here, indicating a slower data processing pace in the memory kit.
To see your voltage decrease and CPU slow down when idle, Speedstep needs to be turned on (it’s set by default). In Windows, your Power Plan should be chosen as "Balanced". The "Performance" plan turns off Speedstep and keeps everything running at maximum, which is inefficient since full performance is restored quickly when needed. This should resolve the issue. Let me know if it works.
burnhamjs :
philipew :
For your voltage to drop and for the CPU to slow down at idle, you must have Speedstep enabled (it is by Default), but also in
Windows
, your Power Plan must be set to "
Balanced
". The "Performance" plan disables Speedstep and uselessly keeps everything max. running which is effectively wasteful and unnecessary as the full performance is given back instantly when needed. Try this and let me know. It should fix the problem.
Ah, yes philipew. I will check this tonight. I remember that the Samsung SSD installed a “Samsung Performance Profile” and that is what it is set to. (Though I thought I remember vcore dropping when I did a baseline before oc’ing. Again- I’ll check this tonight.
philipew :
Your memory kit is fitted with a special chip which keeps in store the JEDEC official tables of working timings. The motherboard will default the memory kit to the chip’s JEDEC timing presets regardless of the XMP profile, so there is no point in loading the XMP profile, better disable it even.
If I DISABLE the XMP profile my memory will run at 2133MHz, 1.2V, 15-15-15-36, whereas if I enable XMP it will run at 3000MHz, 1.35V, 15-17-17-35. (as verified in CPU-Z). Wouldn’t I want to have XMP enabled?
philipew :
"Relax OC" renders all the timings you have set very loose (i.e. "relaxed" to prevent booting problems), but without showing you the result of this action which can also severely downgrade the overall performance of your memory kit.
Ok. I didn’t see any changes to the timing within BIOS but I’ll have to see what CPU-Z is reporting when I have “Relax OC” enabled.
philipew :
I also recommend the following:
CPU EIST Function = Enabled (this is Speedstep – good to reduce temps at idle – both GHz and Volts)
For C-States:
CPU Enhanced Halt (C1E) = Disabled (= C1 Enhanced) - (primitive version of Speedstep)
C3 State Support = Disabled (check that the voltage still drops at idle)
CPU C3/C7 State Support = Disabled (not so useful)
Thanks for all the info philipew
🙂
I’ll give these a try tonight.
Maybe your Corsair Vengeance kit doesn't have the JEDEC memory table chip fitted on my Kingston HyperX Fury memory kit to override the XMP. No big deal to keep it on then... ;-)
I don't think that CPU-Z (or even IBT) will accurately detail the set "Relax OC" timings, but it's worth investigating. In general, the tighter the timings (like a low CAS value for example), the better the performance of the memory kit because these timings are latencies, delays (as you know, 15-15-15-36 is better than 15-17-17-35). The most important factor though is the operating frequency (3000 MHz in your case). As such, going to 3200 MHz would bring a worthwhile performance improvement. But I don't know if your particular kit can run at 3200 MHz.
For the primary timings (CAS, tRCD, tRP and tRAS) like 15-15-15-36, the minimal stable values depend primarily on the memory frequency with voltage playing a secondary role in the borderline areas. However, on Skylake you also have to keep in mind that tRCD must be equal to tRP at all times and that the minimal tRAS value one can set in the BIOS is 28.
By the way, a 1:1 CPU/Cache ("Uncore") frequency ratio tends to raise the temp a little, but also slightly reduces memory latency (1 to 4 %) the higher memory freq. goes above 2133 MHz (2133 - 2333 - 3000 - 4000 MHz). Given your good temps, you could also set it that way. For 4.6 GHz it would then be CPU / Uncore ratio at 46/46 (same multiplier). The Uncore ratio remains at its stock value of 3.5 GHz (i.e. a 1:1 ratio to start with) if you don't manually change it in the BIOS.
Additionally, a 1:1 CPU/Cache ("Uncore") frequency setting usually increases temperature slightly, while also reducing memory latency by about 1 to 4% when the higher memory frequency exceeds 2133 MHz (which corresponds to ranges like 2133 - 2333 - 3000 - 4000 MHz). With your current temperatures, you might be able to maintain this configuration. For a 4.6 GHz setup, the CPU/Uncore ratio would then be 46/46 (using the same multiplier). The Uncore ratio should stay at its default value of 3.5 GHz if you don’t adjust it manually in the BIOS.
For my 4.6 GHz configuration, I have a CPU/UNCORE ratio of 46/45. I also have another post about Gigabyte Offset voltage with all my overclock settings documented.
Thanks again - philipew. I’ll check what CPU-Z displays for memory timings in each setting. If I want to stick with 4.6 GHz, I should use "Relax OC" when applying XMP to reach 3000MHz or avoid overheating. There’s a 10-degree difference between standard XMP and XMP with "Relax OC" enabled.
Here’s a revised version of your text with the same length and structure:
The ratio between CPU and Cache ("Uncore") tends to increase temperatures slightly, while also marginally lowering memory latency by up to 4% when memory frequency exceeds 2133 MHz (with adjustments between 2133 and 3000-4000 MHz). Given your stable temperatures, you might consider this setting. For a 4.6 GHz configuration, the CPU/Uncore ratio would be 46/46 (same multiplier). The Uncore value stays at its default of 3.5 GHz if you don’t adjust it manually in the BIOS.
For my 4.6 GHz setup, I have a CPU/UNCORE ratio of 46/45. I also have another post about Gigabyte Offset voltage with all my OC configurations listed.
Thanks again, philipew. I’ll check what CPU-Z displays for memory timings in each configuration. If I want to maintain 4.6 GHz, I should use "Relax OC" when applying XMP to reach 3000MHz or avoid overheating. There’s a 10-degree difference between standard XMP and XMP with "Relax OC" enabled.
You’re welcome—every setup is unique due to the many involved parameters.
"Relax OC" doesn’t change the BIOS memory timings you set, but adjusts values (such as write recovery time tWR or refresh cycle time tRFC) within the CPU’s Integrated Memory Controller. These are internal settings that help manage data flow between the CPU and RAM under your BIOS parameters.
Otherwise, it makes things much harder, often leading to higher temperatures. With strong cooling (like liquid nitrogen), some builds can handle it—though I’d prefer lowering the frequency instead of risking overheating. Still, you now understand why these adjustments matter.
These configurations might appear in CPU-Z but aren’t very useful for most users. You’ll need to know what you’re doing if you want to change them. Also, not all motherboards support manual BIOS adjustments for IMC settings. My Gigabyte GA-Z170XP-SLI does allow it, even though it matches the same OC levels as more premium boards like the Z170X-UD5.
As you noted, a 46/45 ratio is acceptable, but 46/46 would keep temperatures minimal (something simple to test). Overall, everything seems reasonable.
Enjoy your overclocking and stay safe!