X99 PC works ONLY when underclocked

[Legion_X]

Hi Guys,

I have the "badass" AsRock Fatal1ty X99 Professional Gaming i7 motherboard.

It's a beautiful board, but I have a serious issue.

Same thing happens with my I7 6800K and I7 6900K on this motherboard.

The system works ok only when I UNDERCLOCK the CPUs to about 2500MHZ. Stress testing with PRIME95 and OCCT went fine for an hour or so.
When I try to boot up the system with Default setting (All setting on Auto pretty much), it freezes before getting into Windows.
What I tried to do is add voltage manually (CPUs speeds on auto).
There are two setting I played with : CPU Input Voltage, and VCORE.
When I put CPU Input Voltage on 1.9-2.1V, The system boots up ok, but there are occasional freezes and restarts and when I try to run PRIME95 or OCCT, The system freezes immediately.

The other hardware I am trying to make this damn thing work :
Gigabyte GTX 1070 G1
Sasmsung EVO 850 500GB
WD RED 3TB
Seasonic Focus 650W Gold
Noctual D15

I have few other systems to play with, so I checked all other components and they are working well.

The funny thing is, I sent the motherboard to ASRock because logic told me the problem is in the motherboard, but guess what?
They sent the same motherboard and told me it's working properly.

I would really appreciate if anyone can help me.

 

[whm1974]

Check the HSF compound to see if it dried out, if so reapply. It can also be the CPU.

 

[Legion_X]

Thank you for your reply,

as I wrote I used 2 CPUs, both work flawlessly on another motherboard.

Happy new year.

 

[whm1974]

Reset your BIOS, that might help.

 

[Legion_X]

Reset your BIOS, that might help.

Did that many times while playing with the setting.
Didn't help, but thanks though.

 

[whm1974]

Did that many times while playing with the setting.
Didn't help, but thanks though.

The only thing I can think of is using better cooling.

 

[Legion_X]

The only thing I can think of is using better cooling.

Thank you but temperature is not the problem here.
Better cooling than Noctual D15?

 

[Geforce man]

Power supply issue? Do you have a spare to test? those CPU's @ 2500Mhz consume drastically less power than they do at full speed. Just a thought.

 

[Legion_X]

Power supply issue? Do you have a spare to test? those CPU's @ 2500Mhz consume drastically less power than they do at full speed. Just a thought.

I actually have 3 power supplies.
The one mentioned and Seasonic 1050W Platinum, and Corsair CX750.
Same issue with all of them.

Thank you.

 

[LTC8K6]

AVX offset?

 

[Charlie22911]

Do NOT leave things on auto, there are several cases of people’s CPUs being killed by wonky auto voltage offsets (I’m one of them).

I’d give you some settings to start with for 4GHz but I’m out of town.