Overclocking a 4790k

[trents]

All the bios settings look like they should as far as I can tell. Meatball, you did not win the silicon lottery. You are one of the unlucky ones who got a chip made from a lower quality silicon wafer, comparatively speaking. It is a well-known fact that some of the quad core Haswells would top out at 4.4 ghz. A small percentage will do 4.8 or better.

Read this: http://www.overclockers.com/3step-guide-to-overclock-intel-haswell/ It will give you a flavor for how much these puppies vary in their overclockability.

 

[madmeatballs]

well I guess this is as far as I can get it to then.

 

[trents]

Work at getting it good and stable at 4.4 and then sell the chip at some point to finance another, hopefully better, one.

 

[madmeatballs]

Weird now I'm stress testing 4.5 with 1.25v cpu v and .2 sys agent offset stable for an hour now. Only thing that changed was I turned on the AC of my room. I dont reach 70c at full load but when the ac is off I get mid 70c with this 1.25 voltage. Never seen 80c again after delidding. Ambient now is 23c with AC on 30c without ac
(HWM while running prime95 blend test)

 

[EarthDog]

For 2x8GB 2400 MHz, you shouldn't need to touch SA voltage at all..set it to auto and see if you are still stable.

 

[madmeatballs]

Well, somehow it helps my oc become stable, I'll try it on auto too. Anything else that can help with stability ED?

Edit: I forgot to mention I did something different and left the cache ratio to auto instead of x45 too.

 

[trents]

He's already had it on Auto. That was what he started with.

 

[EarthDog]

That makes almost no sense for that amount of memory and its clockspeed. Must be a weak IMC too...

First for everything I guess!

 

[trents]

Happens!

 

[madmeatballs]

So the motherboard had a weak IMC? or my chip?

edit: stress test with this settings 1.25v cpu v, .2 sys agent offset, auto CPU cache ratio multiplier, x45 cpu ratio. Stable with prime95 been running for a good 10 hours now. Could it be that it was just the cache ratio making my oc unstable? I'll try setting .2 sys agent offset to auto with CPU cache ratio at auto. All of a sudden just turning that CPU cache ratio to auto made my oc stable

last edit:
I am under the impression that I misunderstood what this CPU cache ratio is. Coming from AMD I do not know what it is. As I tried googling around I found out that it isn't necessary to overclock the cpu cache ratio and it does not mirror my cpu core ratio. I've been fooled by that asus north america video on how to overclock haswell. Now, are these true? Glad to see I can still push my chip further as long as my temps stay down.

edit:

Looking at HWMonitor my CPU actually hit 4.6GHz (these are also my temps at 31c ambient)


CPUZ

 

[trents]

Yes, the cache ratio does mirror the CPU ration when the cache ratio is on auto. When you have a really high overclocking Intel Cpu the cache ratio may not be able to keep up with the core ratio beyond a certain point. I'm running my core ratio at 50x and my cache ratio at 40x.

 

[madmeatballs]

Well, I set my CPU cache ratio at x45 along with my CPU core ratio. So it looks like my cache ratio can't keep up with the core ratio. What does CPU cache ratio do anyway? Is it okay to just set it at auto?

I will try 4.6GHz now with cache ratio at auto and I'll be putting back sys agent offset to auto too just to see if the .2 offset is really necessary.

Oh and how do I know what my current cache ratio is if I set it at auto?

Edit: Stressing(prime95) 4.6GHz right now, no immediate BSOD sys agent offset at auto and appears as 0 on hwmonitor.

 

[trents]

If you will download and install Intel Extreme Tuning Utility it will tell you all that info.

Didn't you start out this whole adventure with the cache ratio on auto?

Cache ratio is the same idea as the core ratio. Cache is very high speed memory built into the CPU die. It stands between the cores and system RAM. The processing cores take data from the cache and the cache takes it from the system RAM. Changing the cache ratio changes the speed at which the cache operates just like it does for cores when you change the core ratio.

 

[madmeatballs]

nope, I had my cpu cache ratio at x45 all along when testing x45 core ratio because I had them stable at x44 when my cpu core ratio was at x44 looks like the cache ratio is stable only up to x44?

30 mins into prime95 no bsod x46 core ratio at auto cache ratio without the .2 sys agent offset. cpu v at 1.25v

looking at intel xtu my cache ratio is at x40.

Your cache ratio is at x40 with your x50 oc right? or did I read that wrong?

 

[trents]

So I'm confused! Do you have the cache ratio manually set to 40x or is Auto setting it to that? I was under the impression that Auto will set the cache ratio to the same as core ratio. And didn't I suggest earlier to put your cache ratio at 39 or 40x?

 

[madmeatballs]

Lol sorry about the confusion!

Well, here when I was testing 4.5GHz I had it on x45 manually! Actually the time I started this thread it was manually set with x45 all along. I forgot to put it(cpu cache ratio) on auto when testing the .2 sys agent offset you suggested.

Last night(this morning for you guys?), I randomly tried setting cpu cache ratio to auto instead of x45 and it worked out through a 10hr stress test at 4.5GHz

Now I'm testing 4.7GHz at 1.28v no sys agent offset and my cpu cache ratio is set to auto. Intel's xtu is saying the cache ratio is at x40.

 

[trents]

I'll tell you, these Haswells are as different from one another as night and day sometimes. What works for one doesn't work for another. They're all over the map.

 

[madmeatballs]

Well, I guess the max safe oc for me is at 4.6GHz with 1.25v though I havent reached the 90c I wouldn't want to anyway. Just for the fun of oc'ing I'll continue.

 

[trents]

So it seems your cache ratio was too high all along for that particular CPU and that was the issue. No matter. Raising the cache ratio above stock will have virtually no effect on performance anyway.

 

[madmeatballs]

Okay, it looks like I'm stable with 4.7GHz at 1.35v now. The question is do I want to stay at this voltage lol.