Safe core voltage - 7700k?

[Turbo Ben]

Simple question, but can't seem to find a solid answer anywhere!

What is a safe 24/7 core voltage for the 7700k? I've managed a stable 5Ghz at about 1.32v, but I think there is more to be had. I've delidded the cpu, lapped the IHS and used thermal grizzly conductonaut on the die and the cooler which is a corsair H100i V2. Temps at full load are about 50 degrees, so plenty of thermal headroom!

Any thoughts much appreciated.

 

[PC-4LIFE]

That's a hell of a chip.

Think of 1.4VCore as a max for liquid cooling.

 

[Turbo Ben]

Yeah, almost makes up for the first one I broke attempting the delid lol

 

[PC-4LIFE]

Yeah, almost makes up for the first one I broke attempting the delid lol

And you still did it again. Good luck.

 

[Turbo Ben]

Well, not exactly. I got it off ebay and the seller offered to do it for an extra fiver lol Breaking one is bad enough, two would have been devastating!

Thanks for the reply by the way.

Out of interest, what do people think of Intel's XTU for stress testing? I've just done a quick stress test at 5.1 GHz @1.35VCore and seems OK.

 

[geofelt]

I think you scored a good chip.
Here are silicon lottery stats:
As of 1/13/17
What percent can get an overclock at a somewhat sane 1.4v Vcore.

I7-7700K
4.9 74%
5.0 56%
5.1 26%
5.2 5%

I like to test with occt.
It uses a more normal set of instructions.

I think a peak of 1.4 during a stress test would be ok. The damage point is 1.5v as far as I can tell.

Under normal use, you will not be at stress test levels.
If you use adaptive voltage and speedstep, you will reduce your multiplier and vcore when the cpu has little to do.

You should also look into avx offset which negates the problems when that unusual instruction is present.

 

[Turbo Ben]

Wow, does look like a good chip! I'm running adaptive yes. Set at 1.35VCore, but XTU shows it's more in the region of 1.375. AVX offset is at 2.

I've just encountered some instability at 5.1GHz, so trying a higher AVX offset, lower cache ratio and dropped my memory frequency down.

I'm running BCLK at 102 (to squeeze the last few MHz out of the memory) and a multiplier of 50x. Would I be better putting BCLK back to 100?

 

[PC-4LIFE]

Well, not exactly. I got it off ebay and the seller offered to do it for an extra fiver lol Breaking one is bad enough, two would have been devastating!

Thanks for the reply by the way.

Out of interest, what do people think of Intel's XTU for stress testing? I've just done a quick stress test at 5.1 GHz @1.35VCore and seems OK.

I wouldn't use it. CPU usage fluctuates a lot when using it, which doesn't happen when using Prime95 or other stress tests.

 

[Turbo Ben]

OK, I've spent a little time messing, and I've come accross something else that I'm not sure about. I had a look at the Asus overclocking guide, and it said if using adaptive voltages to set IA AC/DC Load Line to 0.01. I have no idea whatsoever what this does, but I noticed VCore stayed much closer to the value I set rather than overshooting by 0.025V. Unfortunately it also seems to have made things unstable. I set both back to auto and dropped VCore by 0.025V and now all seems well again.

I've done a quick search and can't find anything that describes what these settings do. Can anyone shed any light on it for me, and why do Asus say set them to 0.01?

 

[Karl_10]

I got a good stable 5.0ghz oc at 1.300v on the 7700k. On z270Maximus IX Formula, G-skill trident Z @ 300mhz. Works on both z170 and z270 ROG MOBOS.

Oc profile
OC TUNER set to XMP
BLCK 100
AVX3
Cpu core ratio ( Sync all cores)
Cpu Core ratio (50)
DRAM Timing Control (Maximus treak Mode 2)
External Digi+ power control (Level5)
CPU core/caChe limit max
(255.50)
Min. Cpu cache ratio (43)
Max. Cpu ratio ( 43)
Cpu core/cache voltage (manual mode)
-Cpu core voltage override (1.300v)
DRAM Voltage 1.3500v to 1.400v( Depending on ram Timings)
Cpu VCCIO Voltage (1.2000v)
Cpu system agent voltage ( 1.22500v)
Save to profile
F10

 

[kn0wledge_is_p0wer]

I got a good stable 5.0ghz oc at 1.300v on the 7700k. On z270Maximus IX Formula, G-skill trident Z @ 300mhz. Works on both z170 and z270 ROG MOBOS.

Oc profile
OC TUNER set to XMP
BLCK 100
AVX3
Cpu core ratio ( Sync all cores)
Cpu Core ratio (50)
DRAM Timing Control (Maximus treak Mode 2)
External Digi+ power control (Level5)
CPU core/caChe limit max
(255.50)
Min. Cpu cache ratio (43)
Max. Cpu ratio ( 43)
Cpu core/cache voltage (manual mode)
-Cpu core voltage override (1.300v)
DRAM Voltage 1.3500v to 1.400v( Depending on ram Timings)
Cpu VCCIO Voltage (1.2000v)
Cpu system agent voltage ( 1.22500v)
Save to profile
F10

You need to turn AVX off completely to run the full 5ghz. If you haven't yet realized the AVX offset drops your core clock speed depending on the AVX offset you pick. AVX -3 offest will downclock the CPU 300mhz putting it at 4.7ghz. I have AVX turned off completely and running 5ghz stable at 1.375v

 

[envy14tpe]

Why does liquid cooling allow for higher voltage when compared to even high end coolers like Noctua NH-D15? Is there a typical rule when increasing voltage, to do so safely?

 

[SnoitseuqPi]

Simple question, but can't seem to find a solid answer anywhere!

What is a safe 24/7 core voltage for the 7700k? I've managed a stable 5Ghz at about 1.32v, but I think there is more to be had. I've delidded the cpu, lapped the IHS and used thermal grizzly conductonaut on the die and the cooler which is a corsair H100i V2. Temps at full load are about 50 degrees, so plenty of thermal headroom!

Any thoughts much appreciated.

1.45 max as long as thermals are good. I run 1.36 5.0 24/7 with an h115iAIO. But I also have the cache at 4.6, and it's de-lidded. But it rarely sees 55. LOTS of overhead for OC session,s but I chose 5.0/1.35ish 24/7.

1.45V is safe though as long as your thermals are good.