3200mhz memory instability on Ryzen

PiKe · 27 May 2020 at 16:03

I'm trying to work out why I keep seeing memory errors on the following spec:

Ryzen 7 2700
16gb (2*8) cmk16gx4m2b3200c16 @1.4v (BIOS only goes up in 0.05v steps)
Asrock B450M Pro4-F

The BIOS loads the XMP profile but sets the voltage under spec at 1.35v, I've increased it to 1.4v and I still see an error in memtest86, it just takes a bit longer.

The motherboard is running bios p1.50 as the versions above that say that they are not recommended for pinnacle ridge cpus.

It's listed on the QVL list for the motherboard too.

Any suggestions besides trying a lower memory freq?

tamzzy · 27 May 2020 at 16:16

Ryzen+ (2700) doesn't have the best imc, not all can run ram at 3200 or greater.
Your best bet is to drop the ram speed to 3000

PiKe · 27 May 2020 at 16:32

It's a bit rubbish when the QVL specifically states pinnacle ridge with this exact memory, I've checked the die and it's Samsung b-die so it should have it's best shot at it working :confused:

Jamin280672 · 27 May 2020 at 16:36

PiKe said:
It's a bit rubbish when the QVL specifically states pinnacle ridge with this exact memory, I've checked the die and it's Samsung b-die so it should have it's best shot at it working

Are you sure its Sammy B-Die, download Thaiphoon burner and check with that, because CL16 3200mhz is very very rarely B-Die, its more like Hynix, much cheaper, B-Die is normally CL14 in the 3200mhz flavour

Ive just googled the part number, there is no way in this world that Corsair LPX is B-Die, its cheap ram, and quickly reading some reviews on the rainforest, most people are only getting 2933mhz out of it with 2nd gen Ryzen.

Vince · 27 May 2020 at 16:48

tamzzy said:
Ryzen+ (2700) doesn't have the best imc, not all can run ram at 3200 or greater.
Your best bet is to drop the ram speed to 3000

Does the x have a better imc? I ask as i bought 2 second hand 2700x cpu's and both went straight in at 3200mhz on cheap b450 boards. Both using cheap £35 chinese nanya a-die kits and both pass memtest by only selecting dcop.

Jamin280672 · 27 May 2020 at 16:54

You could try raising the Vcore SoC voltage to 1.100v total, see if that helps.

tamzzy · 27 May 2020 at 17:04

PiKe said:
it's Samsung b-die so it should have it's best shot at it working

lol. buying into hype again.

Vince said:
Does the x have a better imc?

no one's been able to prove it conclusively either way

SonicSW20 · 27 May 2020 at 17:05

Check your RAM voltage. I spent a longer than I'd like chasing a memory issue, and it turned out that while it was running at the XMP profile speeds and timings, it was not running at the 1.35V needed to achieve those speeds - it was running at ~1.2V on auto. Check what your kit asks for and what your board is supplying.

PiKe · 27 May 2020 at 17:23

Jamin280672 said:
Are you sure its Sammy B-Die, download Thaiphoon burner and check with that, because CL16 3200mhz is very very rarely B-Die, its more like Hynix, much cheaper, B-Die is normally CL14 in the 3200mhz flavour

Ive just googled the part number, there is no way in this world that Corsair LPX is B-Die, its cheap ram, and quickly reading some reviews on the rainforest, most people are only getting 2933mhz out of it with 2nd gen Ryzen.

I used Thaiphoon and it said b-die.

I've tried changing the SOC to 1.0v (not sure what the default is?) if that doesn't work, then I'll try 1.1v, if that doesn't work I'll admit defeat and run it at 3000mhz.

Kit needs 1.36v board is supplying 1.4v as stated in OP.

tamzzy said:
lol. buying into hype again.

I bought it based on it being on the QVL, I only found it was b-die when I checked it earlier

Jamin280672 · 27 May 2020 at 17:33

PiKe said:
I used Thaiphoon and it said b-die.

I've tried changing the SOC to 1.0v (not sure what the default is?) if that doesn't work, then I'll try 1.1v, if that doesn't work I'll admit defeat and run it at 3000mhz.

Kit needs 1.36v board is supplying 1.4v as stated in OP.

I bought it based on it being on the QVL, I only found it was b-die when I checked it earlier

I stand corrected, quite shocked too, SoC at 1.0v is about stock, its runs at something like 0.970v, maybe 1.100v will help, it controls the memory controller alone with other things, even AMD recommend bumping it to 1.100v and its always the first move I make when trying to get my ram up to speed, they say the SoC is good up as high as 1.20v but personally I wouldnt go higher than 1.15v

PiKe · 27 May 2020 at 19:31

No good at 1.1 SOC either, so I'm going to try 3000mhz at stock.

tamzzy · 28 May 2020 at 06:13

@PiKe b-die can take high voltages. Try 1.45v? 1.5v is feasible too, but I wouldn't run that for 24/7 use. Also make sure that your vtt is half of the vdimm - not all boards adjust this voltage when the vdimm is adjusted

If vsoc = 1.1v and vdimm =1.45v and still no joy then probs it's most likely a weak imc (not unexpected for ryzen+)

opethdisciple · 28 May 2020 at 12:01

PiKe said:
It's a bit rubbish when the QVL specifically states pinnacle ridge with this exact memory, I've checked the die and it's Samsung b-die so it should have it's best shot at it working

It is rubbish that there is no doubt. But the issue is the IMC on the CPU you have is out of the control of the ram and mobo manufacture. It's a bit of a lottery.

PiKe · 28 May 2020 at 20:18

3000mhz was stable in the end at default SOC voltage and 1.35v on the ram.

Augustus · 29 May 2020 at 01:46

Not all b-die is the super-duper stuff everyone seems to think it is. These kits are 16-18-18 so that tells you they're not that great quality. B-die with these timings behaves more like e-die but can operate well past the frequencies and voltage e-die can.

I found that increasing the dram voltage and reducing VSoC a bit helped me gain stability with this sort of b-die on my LPX. VSoC goldilocks zone was 1.035 on one board and 1.0625 on another. VDimm was 1.39 for two sticks and 1.44 for four sticks so no need to go overboard. I found after 1.44 my stability disappeared. I managed to get 4x16GB running at 3200 on X370/1800X. Took me a lot of testing and changing though but it's clearly doable even on the early stuff.

Something to remember is that the bus impedances matter when moving across memory dividers. It may be you need to change ProcODT a notch to bring stability in as your board isn't doing it automagically. It may even be one of the RTT impedances that needs a nudge. This happens even on high end boards.

While your RAM may be on the QVL, this only means the board has been tested to work with the ram at the listed speeds and configuration, not that the bios will just set it all up for you. The testers will likely have dialled the ram in to the headline specs manually just to save time.

Did you get the 1usmus memory tool to establish a baseline and see if it works? If not, it's here: https://www.techpowerup.com/download/ryzen-dram-calculator/

Joxeon · 29 May 2020 at 08:44

You would most likely find that if you dropped in a ryzen 3000 CPU then the ram would easily run at 3200 if not more with manual tuning.

opethdisciple · 29 May 2020 at 14:33

Joxeon said:
You would most likely find that if you dropped in a ryzen 3000 CPU then the ram would easily run at 3200 if not more with manual tuning.

Yes. When I had my 2700x it took about a year of bios updates to finally be stable at 3200MHz DOCP. Once I upgraded to the 3700x I was able to run 3600MHz on the ram and this was when I was on still on x370.

Sumanji · 3 Nov 2020 at 14:59

Apologies for necro'ing this thread, but think I am having the same problem as the OP...

https://www.overclockers.co.uk/foru...tting-b-die-stable-on-an-x470-board.18900329/

One question I do have for you all - do memory dividers impact performance? I.e. is it better to run at 3000MHz (1:15) rather than 3066MHz (3:44), because the latter is an "awkward" divider)? I remember back in the day on Athlon XP chips, it was sometimes better to run slower RAM speeds on a more standard divider.

(Showing my age here!!)

Cheers,

Su

tamzzy · 3 Nov 2020 at 15:08

@Sumanji dividers don't matter nowadays
For ryzen best to run ram at the same speed as the infinity fabric clock

Joxeon · 3 Nov 2020 at 15:42

Sumanji said:
Apologies for necro'ing this thread, but think I am having the same problem as the OP...

https://www.overclockers.co.uk/foru...tting-b-die-stable-on-an-x470-board.18900329/

One question I do have for you all - do memory dividers impact performance? I.e. is it better to run at 3000MHz (1:15) rather than 3066MHz (3:44), because the latter is an "awkward" divider)? I remember back in the day on Athlon XP chips, it was sometimes better to run slower RAM speeds on a more standard divider.

(Showing my age here!!)

Cheers,

Su

Just run the ram as fast as it go with stability as the FCLK will always be set to match on the 2700X.