Stable Ryzen Overclock

[sbakic]

Hello guys, I am new here and this is my first topic.

I recently bought new PC and I wanted to to my first OC on this parts:
R7 1700x
NZXT Kraken x62
ASUS Crosshair VI Hero (WI-FI)
G.Skill Trident Z C15 3000 2x16GB
ASUS STRIX GTX 1070 OC
960EVO 250GB
850EVO 1T
EVGA 750P2

BIOS 1501

Windows 10 Build 1703

I used these programs to check stability of OCed system in this order:
1. CinebenchR15
2. PassMark
3. RealBench - Benchmark
4. 3D Mark
5. prime95 - Benchmark
6. RealBench - Stress test
7. AIDA64 - Stress test
8. prime95 - (All three stress tests)
9. OCCT - Stress test

For reading temp and voltages, etc I used all the time HWiNFO64 and a few times (CPU-Z, HWMonitor, AMD Ryzen Master and AISuite3)

I read a lot on the internet about overclocking and i understood a few things. After that I tried to OC and failed to get stable system, thus there are couple questions I would like to ask.

I understood that when PC is on idle CPU has VID voltage with low current and on load voltage drops with VID - vdroop with high current. First as they said try with raising core multiplier and go with manual Vcore. On 38x multiplier with manual 1.375V, on load Vcore goes to 1.3V which is too low and it passes a few benchmarks but fails on stress tests. With manual 1.4125V (with 1.4V VID in HWiNFO64) it has max drop to 1.331V on load, where it get stable between 1.375V - 1.395V). But still when it comes to large FFT it drops to 1.331 and I get error code.

After that I tried to overclock RAM to D.O.C.P Standard, with frequency 2800Mhz with DRAM voltage at 1.35V, CPU SoC is Auto (1.05 in HWiNFO64), with CAS 15 and CR 2T (for Auto CR it sets to CAS 16 with 1T, I read that 1T is faster, but 2T is more stable). And for CPU i now set Vcore to offset +0.03125 (because of one video for Newegg studio), I set CPU LLC to 1, and Gloabl C-states Controls Enabled. With these in HWiNFO64: VID 1.325V, Vcore at idle 1.387V, Vcore at load is between 1.337V and 1.387V (min 1.331V), VDDR 1.373V at idle on load 1.395V, SoC 1.05V.

With this offset for CPU Vcore and OCed RAM I passed from top (1, 2, 3, 4, 6, (1h), 7 (1h)). I cann't pass as I understood large FTT tests.

My questions:
1. Why when I set manual Vcore it still drops voltage on load (is it because it works in that way, like explained in this clip)?
2. Why is VID always different for all different Vcore and how to properly measure it?
3. To set offset Vcore formula is VID (or Vcore at idle) - Vcore at load, real question is how to set Vcore offset? What is max range for setting offset Vcore (I read that I should not go above +0.0375 and I should not do - at all)? I watched this
4. As I tested I saw that with higher + offset Vcore I get higher idle Vcore. Is it good to have 1.4+V on idle and at load ~1.35V?
5. What is large FFT test (Like heavy mathematical operations on cpu)?
6. Do my PC needs to pass large FFT tests like prime95 blend test and OCCT test, to be called stable?

Thanks for reading, if I remmeber something I will edit this.

UPDATE 1
So what I have learned about FFTs tests (Q.5 and Q.6 - Answer is: "Yes it should pass large FTTs tests, in order to be stable.").

Small FFTs

FFT stands for Fast Fourier Transform and is an algorithm to compute discrete Fourier transforms for a sequence of n complex numbers (groan, more math – I’m outta here). The Small FFT test loads neatly into your L2 cache so it tests primarily your CPU. Ram will generally only be affected whenever more data has to be fetched into the L2 cache. The small FFT test is good if you’re just looking to give your CPU a good burn in or test your cooling sub-system out. This test will heat up your CPU, so watch the temps.

In-Place Large FFTs

Due to the nature of in-place FFTs, they do a lot of moving data and swapping to and from memory during the computations. So this test gives your CPU a work out along with some of your RAM. It will also heat up your CPU quickly so watch your temps closely.

Blend

Blend will use small and large in-place FFTs so everything (CPU and RAM) gets a nice work out. Unless you use something like memtest to check out your memory, I recommend the Blend setting. Blend, like the other test, does indeed give your system a work out and the temps rise rapidly. Not to be repetitive, but keep an eye on your temps lest the toasty aroma of a burned CPU begins to fill your nostrils.

So when you do OC and other benchmarks, when you are ready for stress tests, you first test Small FFTs, to see if your CPU is stable, after that you can try Blend test (or In-Place Large FFTs then Blend).

FINAL UPDATE

 

So folks I successfully OCed my system. I found that for 38x multiplier my CPU needs 1.337V at load with Large FFTs. So I set offset +0.0125V with LLC3. With this settings I have VID 1.325V, at idle Vcore 1.369V, at load Vcore 1.337V. I didn't like LLC1 and LLC2 vdroop was so high like ~0.050, with LLC3 vdroop is ~0.030 which is much better. Other setting with offset that gives me at load 1.337V is offset +0.0425 with LLC2, but with this settings idle Vcore is 1.4V which i didn't want to have.

I tried 39x multiplier, i think it should work with manual Vcore at 1.4125V with LLC3, but idle Vcore is too high above 1.4V and I didn't want that.

[Jon Jon]

You shouldn't go above 1.35 for long term use.

 

As for everything else, Ryzen does not support dual bank 16GB Sticks of RAM at higher than 2666mhz.

 

I went through this researching before I built my machine. It's currently a limitation that may not be fixed until Zen 2.

 

I am curious about your voltage issues though, as you should be able to hit 3.8ghz easy with a 1700x, but you could have always just lost the silicon lottery.

[sbakic]

Actual problem is voltage drops, and for someones OCed system Vcore, what is actual Vcore under load. I need some experienced people to look at this problem and to help me to set stable offset for Vcore, and how much should i push LLC. From this videos that i have posted i shouldn't even use it or i should use only low level.

[sbakic]

I have one more question! This is still ongoing question after FINAL UPDATE!

 

I understood if I use CPU offset voltage rather than manual voltage, Vcore will go down at idle? I am testing now manual and offset and I don't see that offset goes down on idle, it stays at the same voltage as manual so what I am missing here?