i7-6700K overclock sometimes locks system during video encode

[King Mustard]

Intel Core i7-6700K
MSI Z170A Gaming Pro Carbon
16 GB DDR4-3000
NVIDIA GeForce GTX 1080
EVGA SuperNova NEX750B
Thermaltake Suppressor F51

• Front: 1x 200mm Thermaltake TT-2030 fan
• Rear: 1x 140mm EK-Vardar F3-140ER fan
• Top: 2x 120mm EK-Vardar F4-120ER fans, both on a 240mm liquid cooler radiator

I'm rather new to overclocking.

I have my i7-6700K running at 4.5 GHz (standard is 4.2 GHz).

• CPU ratio: 45
• Ring ratio: Auto
• CPU base clock: 100.00
• CPU core voltage: 1.300v
• XMP: Enabled
• DRAM frequency: Auto

I have run without problems for 6+ months. Games, benchmarks, no problems.

However, sometimes, when I encode a video (various software), my PC locks up, requiring a force-reboot.

All temperatures are fine. CPU generally runs at 65C during peak encoding load.

Do I have my voltage etc. set wrong?

 

[mattyfez]

You could maybe try a voltage bump to see if that stabilises the system, (1.325v or 1.35 for example) as temps are cool.

However if the crash is just when doing a particular task and only occasional, it's hard to pinpoint.

When you did the overclock did you do some stability tests, if so, which ones?

 

[Pocah]

I think the answer here is you first have to find out whether the overclocking is causing it. So go back to default settings on everything and run it for a few months like that. If it fails, then it's not the overclocking, if it doesn't fail then approach the overclocking again but one step at a time. I mean remember that by it's very nature overclocking is not guaranteed to work and just becuase it passes a test doesn't mean it will work 100% with real apps.

 

[ChocAndGray]

A fully stable cpu will not crash during encoding.

What did you do to test stability? Playing certain games for example wouldn’t be enough.

As mentioned test at stock and see if you still crash.

 

[henson0115]

Test at stock, If it's still happening check for a newer bios, update and try again. Not sure if the Intel ht bug affects encoding or not. Doubt it though.

 

[olivier renault]

Encoding using the integrated GPU? I've had this on an overclock, I reduce the OC a notch. But usually, increasing the voltage just a bit can also work. It's best to stress test your OC really thoroughly (24 hours bench, and so on).