Basic questions about voltage, heat, and gigabytes
Basic questions about voltage, heat, and gigabytes
I recently assembled my second PC and decided to experiment with overclocking for the first time. It was a bit of a test drive for my processor before installing all my music applications, mainly to reach a stable frequency without worrying too much about long-term stability.
i7-8700k dellided
Dark Rock Pro 4
Gigabyte Aorus Pro Z390
I noticed that higher voltage tends to increase heat, which could affect longevity, but I’m not sure if it’s just the heat or something else. There are suggestions to keep the Vcore below 1.35v, likely due to thermal concerns. My cooling system is performing well; during a stress test in Gigabytes Extreme Tuning for 4.9GHz all-core at 1.35v, temperatures stayed under 72°C. After adjusting the Vcore slightly to 1.3v, the test remained below 61°C.
So:
- Does voltage alone harm the CPU (within limits), or is it mainly heat?
- How can I more precisely adjust the Vcore on Gigabyte BIOS? It’s set to auto, but sometimes I need to manually enter a value and it rounds up.
- How long should I run tests before confirming system stability?
- Are there risks in undervolting the CPU?
Within reason, not really. It depends on the distance from the issue. With temperatures under control, the *cpu* should remain stable for years. Issues might arise with the VRMs if they aren't built to handle higher voltages and heat buildup. They usually withstand around 105°C. I think the lower end is just a marketing point—check elsewhere to confirm if 1.33V is safe. Tools like HWMonitor can help verify this.
Within reason, not really. Depends on how far down the road you're talking. With temps in check, the *cpu* should be fine for years. Problems can be with the VRMs etc, if they're not designed to sustain higher voltages - and they get really warm. Typically rated for ~105'C.
I believe the round down is just for show? you'd need to verify elsewhere whether 1.33V is taking or not. Something like HWMonitor can be used inside Windows and give you an idea of the voltage being applied.
This is a matter of debate. Some will say 24hr+ of Prime95. IMO, it depends on the workload you intend to use it for. Do you need "stable-stable"? An hour or so of Prime95 or Aida64, some blender & Cinebench runs to verify... that's what I typically do.
Potential instability, but that can be fixed by increasing the voltage back. If you mean physically, then no.
Barty1884 :
Within reason, not really. Depends on how far down the road you're talking. With temps in check, the *cpu* should be fine for years. Problems can be with the VRMs etc, if they're not designed to sustain higher voltages - and they get really warm. Typically rated for ~105'C.
I believe the round down is just for show? you'd need to verify elsewhere whether 1.33V is taking or not. Something like HWMonitor can be used inside Windows and give you an idea of the voltage being applied.
This is a matter of debate. Some will say 24hr+ of Prime95. IMO, it depends on the workload you intend to use it for. Do you need "stable-stable"? An hour or so of Prime95 or Aida64, some blender & Cinebench runs to verify... that's what I typically do.
Potential instability, but that can be fixed by increasing the voltage back. If you mean physically, then no.
Firstly, Thanks! Secondly I have some weird happenings in my HWInfo that I don't understand.
https://imgur.com/a/MZabWl1
-The maximum voltage has gone all the way up to 1.39, way over the 1.30 I set it at in the BIOS. What is that about? Are voltage spikes a normal and "safe" occurrence?
- Also while the Core Clocks maximum stops at 4,902 the average is in the low 3's. Is it normal for an all core OC to fluctuate that much? I thought adding the manual OC on all cores meant it would always be running at 4.9ghz.
(FIXED IMAGE)
There's 'adaptive' voltage, and you'd need to set an offset to control this -- or you can set a static VCore.
Adaptive will allow the CPU to idle at lower voltage/TDP. Static is exactly as it sounds - set to 1.3xV permanently.
That's SpeedStep (EIST) perfectly normal. Allows the CPU to idle at lower clocks/voltages when not really being used.
You can disable it in the BIOS, or you can enable the "High Performance" power plan inside Windows.
There's various power states that can be enabled/disabled. For the outright maximum overclock, you'd probably want to disable.
For daily use though, having it idle lower/drawing less power etc, is certainly not a bad thing.
Barty1884 :
There's 'adaptive' voltage, and you'd need to set an offset to control this -- or you can set a static VCore.
Adaptive will allow the CPU to idle at lower voltage/TDP. Static is exactly as it sounds - set to 1.3xV permanently.
That's SpeedStep (EIST) perfectly normal. Allows the CPU to idle at lower clocks/voltages when not really being used.
You can disable it in the BIOS, or you can enable the "High Performance" power plan inside Windows.
There's various power states that can be enabled/disabled. For the outright maximum overclock, you'd probably want to disable.
For daily use though, having it idle lower/drawing less power etc, is certainly not a bad thing.
What about the spikes? up to almost 1.4v, is that safe and normal? That kind of makes the number I punch in seem like a relative suggestion.. meaning if I set the number to 1.35 I may be spiking up to 1.45?
Depends on the offset. If you're adjusting 1.33V to 1.39V, it's similar to standard settings like 1.25V spiking to 1.31V. The offset remains unchanged. I understand. It seems the offset is something you might adjust for voltage, though I only recall the AVX offset in relation to clock speed changes under AVX loads.