Hello all

I've been having some issues with my CPU temperature (idle temps are fine [~30°C], but under any load it'll spike as high as 95°C playing games like BF1). The temperature changes seem very rapid as well (HWMon will show a spike from ~30°C to ~70° in under a second when the CPU is under load).

CPU isn't overclocked (i7 4790k "Devil's Canyon") and has a Corsair H75 liquid cooler.

The BIOS is running with optimized defaults (GIGABYTE Z97X-SOX Force).

CPU-Z is showing that the core voltage is 1.419v. Am I right in thinking that this is very high for stock settings, and is also possibly the reason for the high temps? I don't know anything about overclocking or messing with voltages, so any advice would be greatly appreciated.

That's extremely high!

Update the BIOS.

That is very high. I would reset your bios and do general setup again (xmp, boot order etc.) to see if that fixes it otherwise you might have to manually set the voltage.

Should be 1.190v

Yeah, that's far too high. It'll most likely be because your CPU volts are set to auto in the motherboard. Try manually setting it to 1.2v and run a stress test like real bench for a few hours. If it crashes, raise it 10mv (1.21v) and continue until stable.

I had a look at the vcore voltage was set to auto. I tried setting it manually (-0.219v), saved and rebooted. The machine shut off almost instantly and then turned back on stating that it failed to boot. Loaded defaults again and it booted up, but again at 1.419v

Change to manual voltage mode rather than offset voltage mode if your going that route

But updating the bios is the better plan IMO.

Are you running XMP ?

I've had exactly the same thing happen in the past, im using the same chip and another gigabyte mobo, my voltages jumped to 1.5v for no reason, when i finally noticed as my games started crashing i just reflashed the bios and it sorted it out.

Like the other guys says setting manual voltage also corrects it but using normal or auto voltage just set it back to 1.5v, so i would just manually set the voltage to 1.2v then just flash the bios to the latest.

Get it sorted fast though as your chip will be degrading faster at high volts, my overclocks required an extra 10mv to get the same speed after i sorted it.

@darket having xmp disabled or enabled appears to make no difference to the voltage, it's 1.419v regardless.

I'll try flashing the bios and see if that works

Hmm sounds like a bios bug, before you flash the bios i would clear the cmos and remove the battery and power cord, hold the power button in for about 30 seconds to alow the system to discharge any residual voltage , load defaults and try again.

I've flashed the bios to the latest revision. Core voltage is now 1.217v (auto [down from the 1.419v]) but it's not stable in Windows. I've completed frozen 3 times trying to write a reply. Another thing I've noticed is that all cores appear to be running at their boost clock speed all the time (4.4ghz reported in BIOS and by CPU-Z). Is this the intended behaviour or is there something else happening here as well?

Just to give you a little extra information. This build is over 2 years old, I bought on Black Friday 2014 from overclockers. As far as I'm aware, it'll have been running at this voltage since bought :/ I've never had any instability issues, and have never experienced any crashing. The only reason I noticed is because I'd moved the components in to a new case, and on a whim decided to install hwmonitor and cpu-z, and noticed the temperatures on load were high (this was with the stock cooler). I replaced the stock cooler with the Corsair H75, the temperatures are slightly lower (maxed at 85°C) but are still too high

Settings windows to Max Performance instead of Balanced in Power Options can cause sustained boost speeds but it wouldnt cause the instability.

Make sure XPM is set in the bios and its using the correct voltage for your ram, if i set optimized defaults it turns off XMP and causes my ram to run at too low volts and because unstable, to ensure its set to the correct volts i have to set an XMP profile and also manually set the voltage to 1.65v.

@BluD would it still show the sustained boost speed in the bios if max performance was enabled in Windows? I've disabled max performance (CPU-Z now shows a core speed which sits at around 800mhz idle) - I didn't even know I had it enabled :/ I've been stable for around 20 minutes now (with XMP enabled, it was disabled after flashing the bios).

Sounds like you are half way there

Hopefully setting the ram to 1.65v like BluD suggested will fix your remaining issue

YOur bios puts the CPU under load so it always shows teh boost speed yeah, also just to clarify check your rams voltage, dont just set to 1.65v, it just thats what my ram uses, XMP will probably set it all for you though, mine is just a special case i believe

I haven't messed around with the ram voltages, there was a profile already available which matches my ram's clock speed (2133mhz, the default with XMP disabled was 1333mhz). Fingers crossed it's all sorted, you guys are life savers.

cool, hope its sorted.

hwmon shows the voltage at ~0.760v (currently idle), min 0.732v, max 1.224v.
max temperature is down from 72°C to 51°C idle (sits at around 30°C).

should i still be worried about the voltage or is 1.224v ok?