EIST and c-states: enable or disable?

[Ace McPlane]

I see a lot of conflicting information on this question. EIST and c-states. Should you enable or disable them for an overclock?

 

i just stress tested both at 4.7ghz 1.245v on an i7 4790k and I noticed my max temps were 2-4 degrees hotter with c-states disabled. That’s about it.

 

here are the various things I’ve gathered about this:

 

some people say that the jump from a low voltage to your set core voltage while starting a stability test or vice versa can cause a misleading blue screen so to turn them off while stress testing.

 

some say that if it makes it blue screen then, they’re uncomfortable having it on at all.

 

some say it doesn’t effect your overclock at full load anyways.

 

some people say it cause an increase in latency.

 

That’s just tip of the iceberg too.

 

Is any of this right because it seems like there’s no consensus?

 

[Jurrunio]

I'm surprised your chip didnt go up in flames at that voltage

 

Both c-state and EIST are power saving tech, allows reduction of clock speed and voltage when the system is not taking much load or no load at all. It doesnt affect operation in full blast.

[Ace McPlane]

7 minutes ago, Jurrunio said:

I'm surprised your chip didnt go up in flames at that voltage

 

Both c-state and EIST are power saving tech, allows reduction of clock speed and voltage when the system is not taking much load or no load at all. It doesnt affect operation in full blast.

Lol, sorry typo. 1.245v

I got lucky with this chip actually. It’s stable at 1.24. I just add a little for comfort. 72 degrees max temp. It’s fine. I could prob hit 4.8ghz if I was braver. Actually I could maybe even lower the voltage more. I’m still testing.

[Ace McPlane]

Do you think maybe some people got this impression because they have their power plan on performance so it doesn’t scale down the clocks with the voltage? 

[MaverickNoob]

I don't know about your chip in particular, but I can say from personal experience with my two FX-8000 class cpus, that C-State add latency and often the cpus won't hit OC speed if c-state is enabled. Hope this is helpful.

[Ace McPlane]

10 hours ago, MaverickNoob said:

I don't know about your chip in particular, but I can say from personal experience with my two FX-8000 class cpus, that C-State add latency and often the cpus won't hit OC speed if c-state is enabled. Hope this is helpful.

I enabled c-states, turbo boost, EIST and it’s still hitting the overclock perfectly. It’s holding steady at 4.7 under load. Latency though. That’s something I’m very interested in testing. Can you suggest a benchmark that would be best for testing this?

[MaverickNoob]

No, sorry. What I mentioned was user perceptible.... Maybe Latencymon.

[Ace McPlane]

On 11/10/2017 at 8:19 AM, MaverickNoob said:

No, sorry. What I mentioned was user perceptible.... Maybe Latencymon.

cool, thanks.