Question Can't run Cinebench at full thread count

[heather_s]

I'm not overclocking, but i ran cinebench to confirm CPU operation while trying to track down a 'shutting off while gaming' problem (updates to windows and nvidia seemed to fix that)

However, cinebench locks up during the test when i select more than 9 threads under 'preferences' even though its an i7 6 core/12 thread CPU.

Only reference to this problem i could find was a guy that hadn't put enough power to his CPU, but i'm sending 1.33 v to the CPU, so no go there. I also have unistall/reinstalled cinebench, all programs off while running, and confirmed all driver updates

Any thoughts on what is going on? Could the CPU be compromised? I'm not having gaming problems per say, but obviously i'm not getting the full rendering capability, which i'd like to maximize.

Specs:
i7-8700k 6c/12t 3.7ghz
ASUS TUF z-370 pro
Window 10
GTX-1070 Ti
Corsair Vengance 2x 16G RAM
EVGA 650 G3 power supply
Samsung 970 EVO SSD + WD HDD
Master cooler heat pipe (only mention this cuz i saw one issue where the liquid cooler was creating problems that were unrelated to temp)

 

[alexbirdie]

I'm not overclocking,

but i'm sending 1.33 v to the CPU, so no go there.

If you do not overclock, less than 1.2 volt for the cpu should be more than enough.
If you google for 8700k and overclocking you will find lot of guys overclock to 4.7 and 4.8 with about 1.25 volt.

That means, 1.33 volt is much too high. I suggest set voltage in BIOS manually, start with 1.2 volt.

If OK-> decrease to 1.19
if NOK-> increase to 1.21

try again and increase/decrease again by 0.01 Volt and so on, until instable with undervolting or stable when increasing.

If you reduce and the instable, add 0.01 again (the last stable value).

If you like to speed up, than you can use steps of 0.02 volt.

 

[heather_s]

Alex,

Thanks for responding, i tried that and was unable to re-boot until i set voltage in bios to AUTO, and then it went back to 1.33v.

I'm a little at a loss because i was reading a PC World article that jives with what you are saying 1.2 to 1.4. I'm definitely not working this too hard --- the cooler fan only goes to high speed intermittently, my temp profiles are always on the low side.

Stumped