DDR5 overclocking (nightmare)

Admin

Administrator
Moderator
Messages
3,990
#1
While CPU and GPU overclocking is relatively straightforward DDR5 overcloking can be an utter nightmare.

As you increase the DRAM frequency you will become increasingly likely to run into some stability issue. These stability issues can be very difficult to find in stability testing so you might think you have gotten your overclock stable only to then later down the line find some stability issue after doing further changes.

Stability issues can be due to the ram dies themselves becoming unstable but it can also be due to the memory controller that is integrated on the CPU or bad signal integrity between the CPU and the RAM. The imc will become a much bigger problem if you run more than 48 GiB of DDR5.

Since the memory controller sits on the CPU heat from the CPU cores can interfer with the imc making it less stable.

Note that trying to boot windows with highly unstable ram is a bad idea since that might corrupt your windows installation beyond repair (to the point where you have to re-install it). Because of that i recommend first booting into linux to do some basic stresstesting to make sure it's not horribly unstable.

https://github.com/amitxv/StresKit
 

Admin

Administrator
Moderator
Messages
3,990
#2
1. Maximizing the DRAM frequency
Your first priority (after inclreasing tREFI to maybe 65528) is increasing the DRAM frequency as high as you can without it becoming unstable.

Increasing the DRAM frequency will also reduce the latency if you keep using the settings that came with the XMP profile. Eventually however some of these timings will become too tight as you push up the frequency higher. The issue then is that you do not actually know which timings (if any) that needs to be loosened if you noticed instability so you might end up having to loosen up all in order to later tighten them up again until you find the culprits.

As you increase the frequency the minimum stable voltages will increase. Unfortunately more voltage also mean more heat which itself can cause stability issues. Too high voltage can also be outright dangerous for components and this remains the case even if your temperatures are all safe. Higher voltage can also result in more signal distortion, especially on cheap motherboards.
The ICs just have a point where the voltage doesn't scale anymore or the scaling even turns negative. It doesn't even have to be temperature related. I have an old B-die kit that runs great with 1.500V but anything more than that and it's goodbye stability. I've literally tested the sticks at under 10C temps and that didn't change anything.
higher voltage can obviously result in less stability, since overvolting is a thing, as it can ruin signal integrity and overall the signal-to-noise ratio (SNR).

It does not always depend on the motherboard, but rather on the CPU sample too, that is also why different CPUs behave differently.
I found the following voltages to result in stability at 6800 MT/s and 64 GiB of ram (dual rank) on the cheapest msi z790 motherboard.

CPU VDDQ: 1.25
CPU SA: 1.195
CPU VDD2: 1.38
DRAM voltage: 1.4
DRAM VDDQ voltage: 1.41

I also had to change ODT settings (34, fine tune mode 2) to pry open a window of stability.

Since the g.skill ram has a terrible heat-spreader i ended up using a fan to keep the ram cool. Unfortunate with raptor lake it's hard to max out that memory in terms of frequency due to the sub-par imc, it really isn't that much better in gear2 compared to zen4 with gear1 when you are using dual rank DDR5.

Note that the motherboard i was using initially limited me to around 6461 MT/s (version A40) but later msi actually fixed that problem (whatever it was) allowing me to get 6666 MT/s stable easily (aiming for 6800 MT/s stable). Note that a bios update is not guaranteed to improve ram stability, it can actually make it worse, with msi pro z790-p and my other hardware A92 >> A40 > A50.

With single rank ram you can start running into imc issues at around 7200 (with raptor lake) and of course it becomes progressively harder to get it fully stable past that.
 

Admin

Administrator
Moderator
Messages
3,990
#3
2. Stability testing
In order to properly test your ram for instability you have to both stress the ram itself but also stresstest the memory controller that sits in the CPU.

I recommend at least using memtest pro (formerly known as hci memtest) and testmem5 to test the ram sticks themselves.

I recommend to at least use stressapptest and y-cruncher VST / VT3 to stress the memory controller on the CPU.

http://www.numberworld.org/y-cruncher/

Older y-cruncher version:
y-cruncher.PNG

Above the BKT, BBP and SFT tests were disabled since the focus was on specifically testing ram stability (and not CPU stability). Y-cruncher does also have options to disable some of the cores/HT which also can be useful for CPU stability testing but not ram stability testing. Note that y-cruncher can miss some stability problems with regard to ram timings (even if you run the mixed test).

The best software to test that the memory timings are stable might be Testmen5 using the 1usmus5 profile.

https://www.dropbox.com/scl/fi/9lzmyvbvs9xkex0l7tvpy/TM5_0.12.3_1usmus25-CoolCMD.zip?rlkey=ztphpbgxsca60hzmj89nzqtz2&dl=0

One problem i noticed is that it will mostly load the E-cores on windows 10 but you can manually fix that by changing the process priority to "high" for at least 8 instances. I have also noticed that it can miss some stability issues which is why you shouldn't rely on just that.

HCI memtest aka memtest pro

Since the tests above are windows tests it will not actually test all of your ram at once, it will merely test most of it. It's recommended that you reboot after maybe an hour and then continue with more testing.

https://github.com/stressapptest/stressapptest

It's made specifically for linux but you can use it on windows via WSL. Use the following command to test 58.59 GiB of ram for 2000 seconds:
stressapptest -s 2000 -M 60000 -m 32 -W --max_errors 1
It stresses the memory controller a lot by doing random copy operations on your ram.

Since it only does copy operations it will fail to find some stability problems with regard to read operations (read performance is usually higher than copy performance in MiB/s).

Prime95 or mprime using the "largest FFT" or "blend" setting.

Linpack Extreme

MemTest64

It's unclear to what extent very rare stability issues with ram is actually a problem for the typical user so you might get away with not doing proper stability testing. I do however believe that you should at least ensure that it's "decently stable" (such as no error during 3 hours of testing), for the typical users (who do not run software that is very heavy on the ram) that should be enough.

But if you run important productivity software where errors can be disastrous you should of course test your ram a lot harder so i would recommend doing 12 to 96 hours of initial testing and then do at least 1 hour of additional testing every week to make sure there hasn't been any degradation causing instability.

You might want to est at different room temperatures (both cold and hot) to make sure there isn't any temperature-related instability that you miss.
 

Attachments

Admin

Administrator
Moderator
Messages
3,990
#4
Tweaking timings
There are a lot of different timings you can configure. These can have a massive impact on performance but if just one of them is too tight you end up with an unstable system.

By default tREFI is often set way to low resulting in a performance loss of around 8%. Higher tREFI is actually better in terms of speed (unlike almost all other timings where lower is faster or same speed).
You can try setting tREFI to 65528 or 130560 and get 6% to 10% performance uplift. This is arguably the first thing you should do when it comes to ram overclocking.

It's recommended that you do save a bios profile each time you change your timings. If you then find a stability issue you just go back one step at a time until the stability issue disappears. The reason for this is that properly stability-testing DDR5 is very arduous, especially when you have more than 32 GiB. It's probably faster not to properly test for instabilities and just move on since you discover it later down the line eventually anyway.

Intel mlc and stressapptest are both accurate for measuring the performance of your ram, this will be useful for seeing if tightening a timing actually improves performance.
 

Admin

Administrator
Moderator
Messages
3,990
#5
Tertiary timings are very important
Having any of these be too high can have a massive impact on performance.

tRDRDDG higher than 8 reduce read bandwidth by at least 15%

TWRWRDG higher than 8 will reduce write bandwidth by at least 15%

https://www.youtube.com/watch?v=pfR-ypILRMc

Try also setting tRDRDSG and tWRWRSG to 16 or less

Try setting tWRRDSG to 64 or less.

sg = same group
dg = different group
dd = different die (same channel, different die)
dr = different rank

The dd timing will only be used if you have 4 ram dimms.
The dr timing will only be used if you have dual rank memory (such as 2x32 GiB).

tWRWRSG at 14 results in worse performance than setting it at 16, that can result in changing it from 14 to 16 resulting in instability due to the higher performance unmasking some other instability.
 

Admin

Administrator
Moderator
Messages
3,990
#6
The importance of a good motherboard
Some motherboard will be able to clock the ram much higher than others. The exact mechanisms for this is a bit unclear.

X61 reported that replacing msi pro z790-p with asus maxiumux z790 apex allowed ram overclocking to 7200 MT/s istead of struggeling to reach stability at 6600 MT/s with 2x32 GiB (dual rank) DDR5 (A-die).

A sign that your motherboard is bad is that you get your ram stable with low CPU VDDQ and CPU SA voltage but then cannot go higher even if you raise these.

One thing you can test is changing which slots you install the ram in. If it's a good motherboard changing to the other 2 slots shouldn't negatively affect how high you can overclock but some motherboard vendors cheap out on 2 of the slots making them worse than useless.

The old asus prime z690-A is limited to just 6200 in single rank operation.

You might think that the msi z690 unify-x would be good since it has just 2 ram slots but it actually isn't that great
M-die Power!!!! This is how tight I could get this kit, very impressed. I literally maxed out the trefi! 7800 was a no go. tried up to 1.7v, no dice. This is getting the same latency as my Gskill A-die at 8200 C36. I think I am returning both my A-die kits and keeping my M-die for a little longer.

Z790 Apex is a BEAST of a board... on my Z690 Unify-x with the EXACT same processor, The best I could get stable on this kit was 7000 C34, now I am doing 7600 C32, lol. Btw, for anyone that is wondering, my MC SP is between 80-82 whenever I check it.
overclock.net/threads/official-intel-ddr5-oc-and-24-7-daily-memory-stability-thread.1794772/page-545#post-29093503
 

Admin

Administrator
Moderator
Messages
3,990
#7
What to look for when buying DDR5
With raptor lake you want to stick to 2 ram sticks. If you want 64 GiB you should buy 2 sticks of 32 GiB each rather than 4 sticks with 16 GiB each.

2x32 will be dual rank which is much harder on the memory controller but it also performs better than single rank at the same frequency. It's actually not clear what the best option is in terms of getting the best performance besides the fact that you get twice the capacity when going with 64 GiB which itself is very useful.

Edit: Single rank seems to generally perform better with very high end intel z790 motherboards provided you do not run out of ram due to the lower capacity.

https://www.youtube.com/watch?v=ghJb0ttZMV4

https://www.youtube.com/watch?v=wPsQ6sqYxHg

lately 2x24 GiB kits have emerged which does seem to overclock as well as 2x16 kits since they are single rank, that might be a good option if you want high ram bandwidth (over 120 GiB/s and also more than 32GiB of memory).

It's also not clear that hynix A-die would be better than hynix M-die. It seems like A-die is worse in terms of timings which is a significant disadvantage and often you cannot even take advantage of the higher frequency potential offered by A-die due to motherboard/IMC limitations.

Samsung memory tends to have the first 3 primary timings be the same such as 6000CL36, 36, 36

A-die and M-die tends to have lower cas latency while the tRCD is significantly higher such as 6000CL32, 38, 38, 38 and 6000CL30, 40, 40, 40

Samsung DDR5 is overall worse than both A-die and M-die and you don't save much/any money by going for the overall inferior samsung DDR5.

So given that there isn't any clear advantage for any type of memory you might just grab the cheapest 6000+ MT/s kit you can find since it's probably going to be good regardless besides the difference in cooling and the minor differences in terms of silicon quality. Simply avoid samsung and micrson, look for 6000CL32 or better.
 

Admin

Administrator
Moderator
Messages
3,990
#8
BLCK overclocking
The BLCK will not only affect the ram clock. It will also make your CPU faster and more efficient due to less voltage being applied relative to the frequency (unless you use static overclock where the voltage is fixed). This is a very good thing to do if possible.

You can find out the max stable BLCK frequency for the CPU simply by lowering the DRAM multiplyer to a lower value to make sure any error you see is from the CPU and not due to you pushing the ram/imc too hard.

BLCK overclocking will sometimes produce very high aida64 read/write/copy figures due to a bug in the software. The actual perormance increase is no more than linear.
6461 25.PNG


BLCK overclocking is very useful if you want to have a very stable overclock. You can simply tune it for maybe 102 BLCK and then when it seems to be fully stable make a second bios profile with the BLCK reduced slightly (such as 101.6), otherwise you might have a ram error occur once every 7 days or something like that.
 

Attachments

Admin

Administrator
Moderator
Messages
3,990
#9
Memory training
It has been difficult to find any decent information regarding what memory overclocking actually does in the case of DDR5 memory but i did find this explanation for DDR4, should be similar with DDR5:

https://www.systemverilog.io/ddr4-initialization-and-calibration

I got the impression that changing the settings in bios to "long training" made the ram more stable but i haven't properly verified this yet. Still this is something you can play around with if you struggle to get your ram stable with acceptable performance.

I have heard that rebooting can make your memory unstable due to it being trained even if you don't actually change anything in bios (due to the memory being trained again in the next boot resulting in the memory working slightly differently) but i haven't verified that myself yet.
 

Admin

Administrator
Moderator
Messages
3,990
#10
Memory stability table at 6461 MT/s 2x32 A-die
I got what seemed like a stable 6461 overclock earlier but it later i discovered stability issues when i tested with higher room temperature. With a lot of effort i was eventually able to get an overclock that passed 23 hours of stresstesting.

DRAM VDD: 1.40
DRAM VDDQ: 1.40
CPU VDD2: 1.38
CPU VDDQ: 1.26
CPU SA: 1.2
BLCK: 101.2

SA PLL SFR voltage: 0.990
MC PLL SFR voltage: 1.02
memory fast boot: slow training

enhanced interleave: enabled
power down mode: disabled

This was done using msi pro z790-p (not recommended) using bios version A40 (A50 was worse).
Code:
          stable  unstable      testing
tCL       30      29(SAT)
tRCD      38      36         
tRCDw     37      36
rRP       32      30           
tRAS      32      24         
tRFC2     496                 

tRFCPB    432     372?
tREFI     65528             
tWR       60
tWR_MR    60
tWTR      8       6(SAT)
tWTR_L    12
tRRD      8       6
tRRD_L    10                 
tRTP      12                 
tRTP_MR   12
tFAW      32
tCWL      28      12??
tCKE      8
tCCD      8
tCCD_L    12
tCCD_L_MR 12

tRDRDSG   16
tRDRDDG   8
tRDRDDR   12

tWRWRSG   16      12? (HNT)
tWRWRDG   8
tWRWRDR   16      14

tRDWRDG   20
tRDWRDG   20
tRDWRDR   20

tWRRDSG   64
tWRRDDG   54
tWRRDDR   14      16??

tWPRE     2
tRORE     2
tWRPRE    48      46?
tRDPRE    16
tPPD      2
tXP       8       4? (HNT)
tXPDLL    16      4? (SAT)
tPRPDEN   2
tRDPDEN   6
tWRPDEN   6
tCDDED    16
tAONPD    0
tREFIx9   255
tXSDLL    64
tCQOPER   0
tMOD      48      42? (SAT)
tZQCS     84      64? (SAT)
tZQCAL    460     420? (SAT)
tXSR      256     42(SAT)
tREFSBRD  92      60(SAT)
tCSH      42      28? (SAT)
tCSL      6
tCA2CS    8
tCKCKEH   11
tCSCKEH   7
tRFM      280     256(HNT)
OREFRI    64

RTL initA 66
RTL initB 65
CHA/D1/R0 62
CHA/D1/R1 62
CHB/D1/R0 63
CHB/D1/R0 63
https://www.youtube.com/watch?v=ba55hKLlfDw

SenseAmp Offset Training: disabled
Early DIMM DFE training: enabled
DIMM RON training: enabled
DIMM ODT training: enabled
Write drive stength/equalization 2D: enabled
read ODT training: enabled
Read Vref Decap training: enabled
VDDQ Training: enabled
Round Trip Latency: enabled
Turn Around Timing Training: disabled

Earlier i did get what seemed like a stable memory overclock but later i discovered CPU instabilities and later i discovered memory stability issues even after i fixed those.

https://www.youtube.com/watch?v=mzELev8nUds

The reason why i initially used 65280 for tREFI is because tREFI9x cannot be set higher than 255 in bios so it's slightly better if 262120 is evenly divisible by tREFI. I later found out that you can push it as high as 65528 due to the actual value of tREFIx9 being one higher than the value in the bios (there was something else causing 65535 to be slightly higher than ideal).

SAT=stressapptest
1680656592712.png


This was tested with stressapptest since y-crunches failed to find stability issue with the following overclock (SAT later found instability after less than an hour):

https://www.youtube.com/watch?v=T9-UEM3PplM

At 6436 MT/s i got the following table earlier.
Code:
           unstable  stable
tCL        28        30
tRCD       36        38
tRCDw      36        37
tRP                  36
tRAS                 36
tRFC       435

tRDRDSG    14        16

tRDWRSG    18
tRDWRDG    18
tRDWRDR    18
https://www.youtube.com/watch?v=_6dk3zI3_74

While this was likely stable timings were pretty lose and i later had trouble getting it stable with tighter timings (until the recent stable 6461 MT/s overclock).
 

Attachments

Admin

Administrator
Moderator
Messages
3,990
#11
Memory stability table at 6220 MT/s 2x32 M-die
These timings were posted by zero989 and i do not know how hard these have been tested for stability.

timings6220.png
 

Admin

Administrator
Moderator
Messages
3,990
#12
Framechasers: you need to find the voltage sweetspot for your CPU
Like me he found that there will be windows of stability for the memory controller voltages that shrink as you go up in frequency and that this varies between CPUs so it might not be stable if you copy voltages from someone else even if he/she has the exact same models of everything.


He also found out that applying the XMP profile might not even be stable at higher frequencies (such as 8000 MT/s) which isn't exactly surprising either.

Note that he isn't actually particularly great when it comes to overclocking, he is mostly good for entertainment.
 

Admin

Administrator
Moderator
Messages
3,990
#13
Settings for 7200 MT/s dual rank on the asus z790 apex
This was provided by the know banned overclock.net user X61. It did pass a moderetely hard stability test at least (he also DMd me screenshot of passing y-cruncher VST for over an hour).

7200.png


The timings themselves are actually pretty bad. It's likely that he has optimized these further since getting banned, it's just that i personally have not had contact with him.
 

Admin

Administrator
Moderator
Messages
3,990
#14
Settings for 7000 MT/s dual rank 2x32
This was tested lightly by DunkZone and no stability issue was found



They found 1.25 to be a good memory controller (CPU VDDQ) voltage which is in line with my findings.
 

Admin

Administrator
Moderator
Messages
3,990
#15
Teamgroup T-Create 6400 (64Gb) DualRanks @ 6800-32
This overclock was achieved by pakhtunov and was subjected to heavy stability testing.

6800.png


Unify-X A.91U1

DIMMA/B DRAM VDD=1.46 / DRAM VDDQ=1.4
CPU SA=1.2 / CPU VDDQ TX=1.32 / CPU VDD2=1.4
VPP=1.8 / CPU AUX=1.8
 

Admin

Administrator
Moderator
Messages
3,990
#16
7800 MT/s stable with eVGA Z790 dark
Yet another example of having to lower the memory controller voltage to get it stable at higher frequencies, he tried 1.35 first and it just never worked so he had to lower it to 1.3

CPU VDDQ: 1.3
CPU VDD2: 1.6
CPU SA: 1.25
DRAM voltage: 1.58
DRAM VDDQ: 1.45
 

Admin

Administrator
Moderator
Messages
3,990
#17
Buildzoid gave up on 8000MT/s
He got it very close to fully stable but just never the full way. This was with single rank 2x16 memory and many compinations of motherboard, CPU, ram. He didn't try the x790 apex though.


He did claim that how you mount the CPU can affect memory stability.
 

Admin

Administrator
Moderator
Messages
3,990
#18
Hardware unboxed confirmed: XMP profiles are trash
We also see that dual rank DDR5 at 5600 was able to beat single rank at 6000 when using the XMP profiles which wasn't exactly surprising.
Maybe the biggest issue with XMP profiles is low tREFI value costing around 8% in bandwidth. It's very easy to change that to 65280 (or 130560) to get around 8% in free performance in minutes (takes hours to properly test for stability though).
1681157437265.png
 

Admin

Administrator
Moderator
Messages
3,990
#20
The pakhtunov ddr5 overclooding guide
He did discover some tips for better ddr5 overclocking

He like me found that you couldn't manually change RTL timings on msi motherboards since that will prevent you from even booting. He did suggest changing "latency timings settings mode" to "dynamic" which i will try later to get 6600+ stable.

SenseAmp Offset Training: DISABLED
DIMM ODT Training: ENABLED
DIMM DFE Training: ENABLED
Write Drive Strength/Equalization 2D: ENABLED
VDDQ Training: ENABLED
Round Trip Latency: ENABLED
Turn Around Timing Training: DISABLED

Example of advice i disagree with is setting tREFI at auto at first, raising tREFI to 65628 is one of the first things you should do when overclocking ddr5, having it lower might mask some instabilities but that will just result in it taking longer to stress-test your system.

I did see that he did the same mistake of me in assuming that the highest possible tREFI without incurring performance penalty from tREFIx9 times 1028 not being nicely divided (with as small remainder as possible) by it would be 65280, i later found out that you can push it as high as 65528.

Copying overclocking settings others used will work in some cases but very often it just will not work. Copying settings from others can however save you a lot time while also providing a lot better performance than merely applying the XMP profile (due to how bad XMP profiles are). Often the XMP profile isn't even stable due to bad motherboard/CPU.
 

Attachments

Admin

Administrator
Moderator
Messages
3,990
#22
2x32 GiB stable at 7400 with Z690 dark kingpin
It was at least decently stable. Tested for at least 3 hours. This overclock was provided by Ivan One
7400c34 cryncher dual.jpg

photo_2023-03-02_10-44-57.jpg
 

Admin

Administrator
Moderator
Messages
3,990
#23
4x16 GiB stable at 7000MT/s with evga z790 classified.
This is the highest 4x16 overclock i have seen so far. Like many others he found that having too high memory controller voltage will make your overclock unstable (sweetspot in his case was 1.26 to 1.28 for CPU VDDQ)


CPU VDDQ: 1.26
CPU VDD2: 1.476
DRAM VDDQ: 1.45
DRAM VDD: 1.45
DRAM VPP: 1.95

1682235752493.png


1682235404468.png


1682235593092.png
 

Admin

Administrator
Moderator
Messages
3,990
#24
Your overclock is never 100% stable
If you run a stresstest long enough you will eventually find an error. It¨s merely a matter of frequency of these errors.

Fundamentally physics isn't deterministic so you can never actually get a 100% deterministic computer. There is also the issue of radiation (icnluding cosmic rays) and this will be a bigger problem when you do not have full ECC memory.


Still if you find an error after say 20 hours of stresstesting that is still a cause for concern since there might be some scenario where errors will show up a lot more often than the rest you ran.

6461-fail.png
 

Admin

Administrator
Moderator
Messages
3,990
#26
2x32 GiB stable at 6132 MT/s with tight timings
Loukiz had a bad motherboard/imc preventing him from even getting 6200 MT/s stable, he was howevere able to push the cas latency down all the way to 26 at 6132 MT/s which is very interesting.

6132.png


dram VDD: 1.545v
dram VDDQ: 1.53v
VDDQ TX: 1.3v
CPU SA: 1.2v
VDD2/VDD_CPU: 1.376v
 

Admin

Administrator
Moderator
Messages
3,990
#27
8200 MT/s stable (2x16 GiB)
This was subjected to lengthy stability testing with 0 hardware errors found
8200-stable.png

8200-settings.png

MickJones archieved this and wrote:

Hey guys - the 9901 Apex bios seems to be the magic bullet for my board. I was having trouble stabilizing 8200 before, but did so easily with this bios. I also tried the newest bios and it was not as good.
 

Admin

Administrator
Moderator
Messages
3,990
#28
2x24 GiB at 8600 MT/s
This was provided by SoldierRBT and passed 22 minutes of y-cruncher VST

8600C38 tight.jpg


This illustrates that 2x24 GiB will overclock just fine. basically the same performance as 2x16 while providing 50% more capacity.
 

Admin

Administrator
Moderator
Messages
3,990
#30
2x16 GiB decently stable at 6200 MT/s 7700x
This interesting overclock was achieved by chewonthis and passed the y-cruncher FFT test

7700x-ram.png


It's unclear if it would also pass other y-cruncher tests.
 

Admin

Administrator
Moderator
Messages
3,990
#32
AMD now support higher DDR5 speeds
Their gear2 mode used to be broken but now it actually works. Of course there is a latency penalty going from gear1 to gear2 but overall performance might still improve.


A lot easier to get stable than 8000MT/s with raptor lake.

1692516534835.png
 

Admin

Administrator
Moderator
Messages
3,990
#33
2x16 GiB testmen5 stable at 7200 with Ryzen 7600x
The following overclock was posted on r/buildzoid
7200-AMD.png


LastUsernameWasBaned wrote

After extensive testing i managed to set up timings to get best performance i could out of this ram kit.
G.SKILL Trident Z5 RGB Series CL34-45-45-115 1.40V F5-7200J3445G16GX2-TZ5RS
RYZEN 5 7600X @ 5.7GHZ
ASUS X570-P with 1654 bios – newest agesa 25/08/2023
Infinity fabric clock at 2100mhz
TRFC 480 @ 133,33 ns
These were best timings i could reach and still be stable in games and in overnight TestMem5.
If anyone has further suggestions let me know.. I will be testing further with increasing ram speed from here..
I also managed to do a 8000mhz stable ram frequency but timings were so horrible it was not even worth it.

https://hwbot.org/submission/5325923_delvechio212_memory_frequency_ddr5_sdram_4000_mhz

Memory Timings
CAS Latency (CL) 36T
RAS To CAS Delay (tRCD) 46T
RAS Precharge (tRP) 38T
RAS Active Time (tRAS) 36T
Row Cycle Time (tRC) 72T
Row Refresh Cycle Time (tRFC) 312T, 2x Fine: 192T
Command Rate (CR) 1T
RAS To RAS Delay (tRRD) Different Rank: 0T, Same Bank Group: 8T, Diff. Bank Group: 4T
Write Recovery Time (tWR) 48T
Read To Read Delay (tRTR) Different Rank: 12T, Different DIMM: 6T, Same Bank Group: 6T, Diff. Bank Group: 1T
Read To Write Delay (tRTW) 18T
Write To Read Delay (tWTR) 7T, Same Bank Group: 22T, Diff. Bank Group: 6T
Write To Write Delay (tWTW) Different Rank: 15T, Different DIMM: 7T, Same Bank Group: 6T, Diff. Bank Group: 1T
Read To Precharge Delay (tRTP) 12T
Four Activate Window Delay (tFAW) 20T
Write CAS Latency (tWCL) 34T
Write RAS To CAS Delay (tRCDW) 46T
Refresh Period (tREF) 65535T
 

Admin

Administrator
Moderator
Messages
3,990
#35
surprising you are so much into overclocking while neglecting cooling of the machine.
One big advantage with air cooling is not having to worry about leaks.

Watercooling is a bit messy, i still have not put my custom loop back up running.

Adding more cooling to ram doesn't typically help much since you are usually limited by the memory controller on the CPU, expensive ram is basically a scam since it doesn't overclock much better than say 6000CL32.

Your motherboard may also limit DDR5 overclocking, i should have bought a different motherboard i think.
 
Top