[Sammelthread] Samsung 8Gbit DDR4 C-Die K4A8G085WC - OC-Ergebnisse im Startbeitrag! [updated]

[Reous]

@zkyez
I would try to change the timings with the most performance improvment

tRRDS: 4
tRRDL: 6
tFAW: 16
tRFC: 576

@rwdmachine
Sehr schönes Bericht In der heutigen Zeit nicht normal, dass noch jemand freiwillig diese ICs verwendet.

 

[emissary42]

Mein System:
AMD Ryzen 5 3600 (UV Offset Vcore -0,075V)
ASUS Prime A520M-K
Samsung 2x 8GB 2400MHz CL17 (M378A1K43CB2-CRC)

Werte OC (DDR4 3600 CL18 1.25V optimiert)
...

Sieht gut aus. Hab ich mit im Startbeitrag verlinkt

 

[zkyez]

@Reous so I took your advice and changed my timings as attached. Had to increase tRFC to 594 to prevent reboots during operation and decreased the memory voltage to 1.28v. Ended up decreasing latency a bit compared to my latest results which was nice. Went through 6 hours of memory stress test with TestMem5 using anta Extreme config and 1usmus. Seems this memory does not really like heat as 1.35v would error out in 5 minutes, 1.32 would error out after 20 minutes but 1.28 was stable during the stress testing.

 

[Vyvertyt]

Hey i'm new here)
So, I have C-die gskill kit and tried to overclock with the ryzen 2600, but could not get the frequency higher than 3200 XMP, 3333 cl16 always gives an error in the first minutes of testing, so i just made tighter timings on 3200. Is there anything else I can do? I think my 2600 has problems with higher frequences

 

[NovationX]

Hello guys, sorry for writing in English but I really do need help. Recently I built my first computer after 6 years the specs are MSI B450 Gaming Plus MAX, Ryzen 5 1600AF, and 16GB of Corsair Vengeance RGB Pro mainly. I tried to overclock rams many times but it didn't then suddenly I learned 4.31 being samsung b die and 4.32 being samsung c die in these kits and I quickly understood why I couldn't overclock my ram. Then I tried using memory try it from bios which is 18-20-20-38 @ 1.4V you can see it from the attachment. Though I heard that in c die beyond 1.35V is bad thus I need your recommendation. Thanking you in advance.

 

[emissary42]

3333 cl16 always gives an error in the first minutes of testing, so i just made tighter timings on 3200. Is there anything else I can do?

You can use CL18 to test max frequency and rule out the the memory itself not being able to scale higher. S8C usually does 3600 no problem, but with GDM enabled you are often left with CL18 at higher frequencies, since most kits won't be able to scale that far with CL16 and CL17 gets rounded up to CL18 anyways.

Though I heard that in c die beyond 1.35V is bad thus I need your recommendation.

Some modules are fine at voltages above 1.35V and can scale up to 1.4V and very rarely even beyond that. So unless you have issues with stability, there is no need for concern. If you went straight up to 1.4V however, I would recommend testing if that much voltage is actually required (and lower it otherwise).

 

[NovationX]

Some modules are fine at voltages above 1.35V and can scale up to 1.4V and very rarely even beyond that. So unless you have issues with stability, there is no need for concern. If you went straight up to 1.4V however, I would recommend testing if that much voltage is actually required (and lower it otherwise).

Sadly that didn't work I tried lower voltages but error after error popped out too. Tried to follow this guide but couldn't get stable OC at 3600MHz. Though XMP 1.35V @ 3200MHz 16-18-18-36 works fine. Now I am stuck at endless loop and don't know where to start, I started to consider returning these kits because they started to haunt me 😢

 

[emissary42]

Stability at 3600 shouldn't be that hard to find. If you can't stabilize 20s, you might have to go up to tRCD/tRP 21 though. In general with S8C keeping the memory voltage low, gives you more headroom for stability at higher frequencies. So avoid just dialing in a certain value from the top of your head and instead test the actually required voltage properly (from low to high).

For your guidance the first post and the last pages have screenshots with settings from other users. Just keep in mind that 1:1 copying memory overclocks from other setups usually does not work and that some adjustments and stability testing will be required.

 

[Vyvertyt]

You can use CL18 to test max frequency and rule out the the memory itself not being able to scale higher. S8C usually does 3600 no problem, but with GDM enabled you are often left with CL18 at higher frequencies, since most kits won't be able to scale that far with CL16 and CL17 gets rounded up to CL18 anyways.

Unfortunately, cant even boot on 3600 cl18, 3466 too, tried different voltages but nothing helps, seems like 3200 cl16 is max for my kit

 

[emissary42]

That is very unlikely, since even the unbinned OEM modules don't have trouble with 3600 at all. I did test a lot more of them than the ones whose results are in the first post. Overall scaling seems pretty consistent up to that frequency with only some variance in min timings and the required voltage.

 

[Vyvertyt]

That is very unlikely, since even the unbinned OEM modules don't have trouble with 3600 at all. I did test a lot more of them than the ones whose results are in the first post. Overall scaling seems pretty consistent up to that frequency with only some variance in min timings and the required voltage.

Really weird, anything above 3200 is unstable, even 3266. Find out that timings i posted before is unstable in TM5 Extreme, idk this memory is a joke for me) Back to XMP 3200 16-18-18-38-75-560 for now, maybe i should try some different settings im out of ideas)

 

[Krümel]

Really weird, anything above 3200 is unstable,

I think that is because of Your Ryzen 2600.
The RAM is Sure capable of higher speed, but the RAM Controller of Your CPU is not.

 

[Vyvertyt]

I think that is because of Your Ryzen 2600.
The RAM is Sure capable of higher speed, but the RAM Controller of Your CPU is not.

Yeah, seems like youre right. so i will try to do something with timings only, I will not touch the frequency anymore

 

[emissary42]

The first post has screens with full settings from Reous with a 2700X and up to 3800. Even if your 2600 is a bit weaker and you have to settle with less than 3600, it will probably be pretty close (3466/3533).

 

[Vyvertyt]

The first post has screens with full settings from Reous with a 2700X and up to 3800. Even if your 2600 is a bit weaker and you have to settle with less than 3600, it will probably be pretty close (3466/3533).

Only 3400 will boot on cl18 but very unstable, 3466 blue screen on boot and its worse than 3200 cl16 in latency test, maybe its just bad binned memory kit

 

[emissary42]

Did you adjust voltages, RTTs, ProcODT etc or were all those settings still on AUTO?

I find it very unlikely that either your CPU, MB or memory have trouble with 3466. It is probably more an issue of getting the settings right. And yes, it can take time and patience to get a specific overclock fully stable.

 

[Vyvertyt]

Did you adjust voltages, RTTs, ProcODT etc or were all those settings still on AUTO?

I find it very unlikely that either your CPU, MB or memory have trouble with 3466. It is probably more an issue of getting the settings right. And yes, it can take time and patience to get a specific overclock fully stable.

1.35 voltage sweet spot for me, <1.32 or >1.38 wont post, ProcODT 53.3 default, tried lower (40-48) and it become worse >68 too, but it never helps to stabelize memtest, same errors. Only timings makes difference, but on 3400 even cl18 is unstable somehow, maybe i should try change some RTTs if it helps, its hard for me)

 

[emissary42]

It definitely helps setting everything (voltages, CADs, RTTs, etc) manually, esp on lower end boards. Higher end motherboards tend to have more adavanced & robust memory training, so you can sometimes get away with not adjusting everything by hand.

 

[zagreus1]

Hallo Leute, hoffe es geht allen gut! Geniale Arbeit an dem verfluchten C-Die, das ihr Leute macht!
(just ran out of German right there...)

I have extensively read trough the entire thread many times and I wanted to ask something regarding my particular case. I have 64GB (4x16GB CMW32GX4M2E3200C16 Corsair Vengeance RGB Pro v4.32) on an MSI MPG X570 Gaming Edge WiFi with a Ryzen 3950x (please don't ask how I got this crap MB/RAM combination, it's a sad story...). I have been trying to stabilise it at 3200 with voltages between 1.35V-1.4V and of course it wouldn't work, until I found this forum and learned about the <1.35V preference of this RAM. I have made extensive notes on how to attack the issue and finally stabilise my RAM at 3200 or ideally at 3600, but I am currently on vacation and away from my PC (it's a dedicated video editing PC by the way, zero games to be played there), so I am actually preparing myself for when I get back.

What I haven't seen here is a use-case like mine (4x16GB) and my questionsare the following:

1. Will the timings I see from users with less total amount of RAM be applicable for 64GB or do 4X16GB timings need to be even looser?
2. Is 3600 possible in my case or should I concentrate on a lower frequency (3200, 3466, 3533)? And if 3600 is possible, should I completely forget about 3800?
3. For 4x16GB does VDIMM, SOC, VDDG need higher voltages (eg 1.35V, 1.15V) or it doesn't matter?
4. Is there a preference for ProcODT, Rtt etc to be on the higher or lower side of what I see for 16-32GB of total RAM?

My main goal is to have a rock solid PC for video editing, but since I am a compulsive tweaker, I would also like to squeeze every little bit of power I can get from it. But stability is by far the most important thing for me.

Here are my current stable-ish settings.
VDIMM=1.35V NB/SOC=1.05V set at BIOS, however HWInfo shows higher values in Windows for VDIMM.

Any help would be much appreciated!
Dreitausendsechshundert danke !!!!!!!!

 

[athosdewitt]

Hello fellows overclockers is there a regression of performance if i manage to tight some subtimings too much? is it too much a thing? like higher ns , lower fps in games etc? is it stable in memtest5 with 1usmus profile!

i'm stuck with 3000 tight since my ryzen 5 2600 doesn't like fast dual ranked 32gb OEM samsung c-die

it's stable cl16 3200 too but with gdm on and with some subtimings higher, i would like to avoid gdm on since gdm off it's unstable even with loosen main timings and rest on auto like tcl 18-20-20-20-40 18-22-22-44 tcwl 18 etc.

so i'm interested to know what should i increase if it's the case to get lower ns and better overall performance without touching trfc that shit consume souls and it's crap on c die.

Thank you!

 

[athosdewitt]

UPDATE: IMPROVE ADAPT OVERCOME? apparently my kit can do cl15 3066.. with most B-die rated subtimings kill me now. Makes me wonder how much i can push these babies with zen3 instead of this donkey ass zen+ that barely post 3400.

 

[athosdewitt]

you can notice here a much lower ns with loosen tRAS tRC tRRDL +1 and TFAW is new tRRDL X4 and idk why, can someone explain this behavior?

 

[Vyvertyt]

you can notice here a much lower ns with loosen tRAS tRC tRRDL +1 and TFAW is new tRRDL X4 and idk why, can someone explain this behavior?
Anhang anzeigen 655787

Seems like it will be better with 3200 cl16 with gdm on, your current settings 100% stable? SCL 2 is impossible for my kit, try TM5 Extreme test

 

[athosdewitt]

Seems like it will be better with 3200 cl16 with gdm on, your current settings 100% stable? SCL 2 is impossible for my kit, try TM5 Extreme test

Currently i'm at work 3200 throws too many errors and very early in tm5 with gdm off, i'm afraid to run it with gdm on even if doesn't give any errors.. i have to loose some of the timings too like SCL doesn't even boot at 3 with 3200.
Anta extreme or 1usmus what should i chose for SCL 2 3000 / 3066 i had only like 5 min time to check just for curiousity some tight timings i just stopped when i notice an increase of ns because allegedly too tight ? Idk that i've asked in first place becauee it's just wrong, lol

 

[zagreus1]

What I haven't seen here is a use-case like mine (4x16GB) and my questionsare the following:

1. Will the timings I see from users with less total amount of RAM be applicable for 64GB or do 4X16GB timings need to be even looser?
2. Is 3600 possible in my case or should I concentrate on a lower frequency (3200, 3466, 3533)? And if 3600 is possible, should I completely forget about 3800?
3. For 4x16GB does VDIMM, SOC, VDDG need higher voltages (eg 1.35V, 1.15V) or it doesn't matter?
4. Is there a preference for ProcODT, Rtt etc to be on the higher or lower side of what I see for 16-32GB of total RAM?

Anyone?
@emissary42 maybe?
...crickets...

 

[emissary42]

1. Will the timings I see from users with less total amount of RAM be applicable for 64GB or do 4X16GB timings need to be even looser?
2. Is 3600 possible in my case or should I concentrate on a lower frequency (3200, 3466, 3533)? And if 3600 is possible, should I completely forget about 3800?
3. For 4x16GB does VDIMM, SOC, VDDG need higher voltages (eg 1.35V, 1.15V) or it doesn't matter?
4. Is there a preference for ProcODT, Rtt etc to be on the higher or lower side of what I see for 16-32GB of total RAM?

1) In general timings shouldn't differ much, but other settings like CADs, RTTs etc can/will require adjustments esp compared to 2x8GB.
With 4x16GB additional limitations might apply due to the motherboards capabilities and DIMM layout.
2) It should be possible. Active cooling can be required, depending in load temperatures.
3) Depends on CPU/MB mostly, usually does not require big adjustments.
4) Try to keep ProcODT low, unless you have to increase it for stability (progressive with frequency).

you can notice here a much lower ns with loosen tRAS tRC tRRDL +1 and TFAW is new tRRDL X4 and idk why, can someone explain this behavior?

In general there is two possible reasons for performance degradation by over-tightened settings:

1) With unstable settings DDR4 error correction will kick in, which reduces performance.
2) Setting non-viable values for certain timings can require the motherboard to automatically adjust them/others according to memory training rules (can result in some to be considerably higher).

 

[zagreus1]

1) In general timings shouldn't differ much, but other settings like CADs, RTTs etc can/will require adjustments esp compared to 2x8GB.
With 4x16GB additional limitations might apply due to the motherboards capabilities and DIMM layout.
2) It should be possible. Active cooling can be required, depending in load temperatures.
3) Depends on CPU/MB mostly, usually does not require big adjustments.
4) Try to keep ProcODT low, unless you have to increase it for stability (progressive with frequency).


In general there is two possible reasons for performance degradation by over-tightened settings:

1) With unstable settings DDR4 error correction will kick in, which reduces performance.
2) Setting non-viable values for certain timings can require the motherboard to automatically adjust them/others according to memory training rules (can result in some to be considerably higher).

Thank you for the reply!
Meanwhile I discovered this unlisted Buildzoid video where although not using C-die, he tackles 64 GB and the difference between 2 and 4 sticks with different RAM kits

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When I get to my PC I will post my findings here.
Thanks again

 

[athosdewitt]

In general there is two possible reasons for performance degradation by over-tightened settings:

1) With unstable settings DDR4 error correction will kick in, which reduces performance.
2) Setting non-viable values for certain timings can require the motherboard to automatically adjust them/others according to memory training rules (can result in some to be considerably higher).

i had no errors with TFAW 16 and TWR 10 but sometimes pc freeze just once on first cold boot or after ''sleeping'' mode and no issues with bellow new timings

much obliged for your tips mr emissary42
i've read somewhere else some suggestions for OC RAM with a Ryzen CPU.. and goes like this: let me know if any or some of this is true

1. tFAW must be set by tRRDL x4 instead of tRDDS x4 for stability reasons ( by default at 2666 it's 7x4=28 ) and TWR must be double of TRTP = TWTRL so if both are set to 10 TWR is 20. ( again it is indeed like this by default )
2. tRDDL must be 6 at minimum if i go lower it will affect performance in rare situations
3. TRTP even if can be set to 5 it's recommended at minimum of 8 and at or above 12 if speed is 3600 or higher​

Beitrag automatisch zusammengeführt: 08.08.2021

Seems like it will be better with 3200 cl16 with gdm on, your current settings 100% stable? SCL 2 is impossible for my kit, try TM5 Extreme test

SCL 2 100% stable at 3000 and for 3066 i have to retest with current subtimings because with older i had some strange infinite loop in TM5 albeit no errors i've waited 3 hours to finnish what usually takes 45 min.

 

[Alastair_S1D]

Hello there. I am a new user who found this forum thanks to other forums like overclock.net and also a lot of google searching. This seems to be the most COMPREHENSIVE thread of C-die owners with overclocking results on the entire web. I am still reading through this thread there is a lot of information to take in.

So I come seeking assistance. I have Samsung C-Die in my Rig. I have 4x8GB Avexir Core 2 3600 18-20-20-20-44 memory and the IC's are K4A8G085WC-BCTD

Here is the 3600 XMP profile

I obviously want to overclock these further than just stock XMP.
I have :
Ryzen 3800X
Gigabyte Aorus X570 Pro Wifi
4x8GB Avexir Core 2 3600 18-20-20-20-44

Firstly I think I am already VERY close to the limit of this memory as sometimes its not even stable at XMP. But I think the motherboard is at fault for that. I say this because the gigabyte motherboard is very aggressive with the voltages.
If I SET VDIMM to 1.35v I get 1.38V
I I SET DRAM VTT to 0.6V I get 0.67V
I dont know how aggressive my board is being with the DRAM VPP voltage as well I cant seem to see if I can monitor it in HWIFNO

I know C-die is very voltage sensitive above 1.35V. But is C-Die also sensitive to the secondary voltages as well? And how best to set the secondary timings.

I want to TRY get 3700MHz( 101x18.66x2). If I cant I will go for 3636MHz (101Mhz x 18 x 2 DDR) i use 101BCLK to get more boost out of my Ryzen.

Also I am not very knowledgeable about secondary and tertiary timings. I can do primaries but that's as far as my knowledge goes. I didn't bother with secondary timings back in DDR2 and 3 days. Things like timings being in a ratio or in sync with one another. I've seen forum posts saying TRP, TRC, TWR, TRTP and TRFC being linked somehow? Or TRFC is a multiple of TRC. Or TRC is TRAS+TRP. I feel a bit out of my depth. In the DDR3 days I didn't bother with secondaries or tertiary's. I aimed for my primaries and that was that.

Also how does C-die Respond to ProcODT and also Drive strengths?

 

[emissary42]

@athosdewitt Timing rules do exist. Some of them are soft rules, that can be broken, but can/will show reduced performance. Others are hard rules that get automatically corrected by the motherboard during training for very practical reasons. In general those rules are not* IC specific, so I don't want to go into detail about them, plus there are other resources available that thoroughly cover. For non-german users this is a good starting place for general information: https://github.com/integralfx/MemTestHelper/blob/oc-guide/DDR4 OC Guide.md#tightening-timings

@Alastair_S1D Since S8C can have a low voltage threshold and will show a rollover effect if pushed beyond, I would recommend starting with less than 1.35V (real) and normalized VTT. Going up in frequency will eventually require adjusting at least tRCD, tRP and tRFC, while the required voltage usually keeps hovering around a certain value. The last pages of this thread and first post have screenshots from other users with full timings, RTTs etc at DDR4-3600 for orientation. The memtesthelper guide I just linked also answers most of your questions regarding general timing interactions.

ps: welcome to Hardwareluxx