[SOLVED] DOCP doesn't seem to work anymore since RAM upgrade ?

[jorendebruyne]

Hi all


I had 16 gb ram since my last pc upgrade: G.skill ripjaws ddr4 3200 (F4-3200C16D-16GVKB). (2x 8gb)
Recenly I found someone selling this exact RAM: 32 gb for 60 euro.

I bought it. My friend has the same ram too so I thought we could split the price. 30 euro for 16 gb ram is cheap.
My 'old' Ram and the ram I bought are the exact same: same speed, both cl16, same model nr.

So I installed the RAM i bought and my pc didn't want to boot. I disabled DOCP and it booted correctly, 32 gb RAM at 2133.
After this, i wanted to re-enable DOCP but I just can't make it work, I think.


In this link a few images:

• image of my bios. DOCP is enabled. My pc boots fine as long as the 'Memory frequency' is on auto. As soon as i put it on '3200' it won't boot. I'm pretty sure it was on 3200 when i just had my 2x 8gb ram.
• Images of CPU Z (memory and SPD tab)
• Images of hwinfo

https://imgur.com/a/H3BR6v4

View: https://imgur.com/a/H3BR6v4



Command prompt shows 2133 as does task manager.
Is my DOCP working now or not? Totally confused.

Help would be greatly appreciated

 

[MeanMachine41]

When DIMMs are manufactured they are binned into matching sets due to slight variations in Latency/Density or you might say the Quality of the Silicon chips used.
It is an extremely precise process.

Even RAM kits with exactly the same frequency and CL can mismatch and Manufacturers warn of this. You should never mix ram. Some try for budgetary reasons only to find what you are experiencing. Sometimes it works however most times it don't and sometimes the system boots but at a lower than rated frequency.
Sometimes the system won't boot at all or you get sudden or random reboots.

Yes I understand this was not your intent however that is where your at and you made a mistake.

During the POST cycle your RAM is interrogated and a safe set of SPD values are assigned. If Bios is confused then it will assign values that conform with JEDEC standards which may work or may not.
I bet if you put the system back to how it was before you added the extra RAM, the system would work OK again.
Follow the rules and get a kit the size and frequency your CPU and Motherboard supports in a single kit that are listed on the MB QVL and that way you know they are tested and known to work. OR accept what does work at 2133Mhz and if issues arise in the future you will know why.

 

[Bob.B]

Hi all


I had 16 gb ram since my last pc upgrade: G.skill ripjaws ddr4 3200 (F4-3200C16D-16GVKB). (2x 8gb)
Recenly I found someone selling this exact RAM: 32 gb for 60 euro.

I bought it. My friend has the same ram too so I thought we could split the price. 30 euro for 16 gb ram is cheap.
My 'old' Ram and the ram I bought are the exact same: same speed, both cl16, same model nr.

So I installed the RAM i bought and my pc didn't want to boot. I disabled DOCP and it booted correctly, 32 gb RAM at 2133.
After this, i wanted to re-enable DOCP but I just can't make it work, I think.


In this link a few images:

• image of my bios. DOCP is enabled. My pc boots fine as long as the 'Memory frequency' is on auto. As soon as i put it on '3200' it won't boot. I'm pretty sure it was on 3200 when i just had my 2x 8gb ram.
• Images of CPU Z (memory and SPD tab)
• Images of hwinfo

https://imgur.com/a/H3BR6v4

View: https://imgur.com/a/H3BR6v4



Command prompt shows 2133 as does task manager.
Is my DOCP working now or not? Totally confused.

Help would be greatly appreciated

A test.
Remove your orig ram and install the new 32GB ram.

 

[--SID--]

You want to use 3 dimms, your original 2x8GB and 1x16GB? Don't do that with Ryzen. Only use RAM in pairs so 2 dimms or 4 dimms with the same specs and from the same batch. Best you can do is sell your current RAM to your friend and keep the 2x16GB yourself.

 

[kerberos_20]

xmp/docp is tuned for just those sticks that you buy, if you buy set of 2 sticks, values will be tuned for 2 sticks

try increasing tRFC number in ram timing settings, 374 might be too low for 4 sticks, try with 800 if it POSTs, if yes, feel free to reduce it
more ram you have, higher number needs to be there

you may also need to change some other subtimings/voltages if tRFC wont be enough

 

[jorendebruyne]

xmp/docp is tuned for just those sticks that you buy, if you buy set of 2 sticks, values will be tuned for 2 sticks

try increasing tRFC number in ram timing settings, 374 might be too low for 4 sticks, try with 800 if it POSTs, if yes, feel free to reduce it
more ram you have, higher number needs to be there

you may also need to change some other subtimings/voltages if tRFC wont be enough

Thanks for the tips. I have never modified my BIOS in this way so it was rather hard to find did some tests but it didn't boot. Maybe it's just me, i didn't really knew what i was doing

A test.
Remove your orig ram and install the new 32GB ram.

I thought it wouldn't matter... But it did!
My RAM was produced 04/2018 the RAM i now bought has two sticks from 07/2019 and two from 10/2020.

I took my old ram out and replaced it with the new ones and everything seems to work perfectly now. running at 3200Mhz!
The 4 sticks of the Ram i bought doesn't seem to be from the same kit, but sometimes you just have to get lucky i guess?

(I don't really know what to do with my friend now, i'll try with my old ram but i guess it won't boot. Maybe he won't mind running at 2133...)

Thanks all! I'm a happy gamer again.

 

[DSzymborski]

Thanks for the tips. I have never modified my BIOS in this way so it was rather hard to find did some tests but it didn't boot. Maybe it's just me, i didn't really knew what i was doing



I thought it wouldn't matter... But it did!
My RAM was produced 04/2018 the RAM i now bought has two sticks from 07/2019 and two from 10/2020.

I took my old ram out and replaced it with the new ones and everything seems to work perfectly now. running at 3200Mhz!
The 4 sticks of the Ram i bought doesn't seem to be from the same kit, but sometimes you just have to get lucky i guess?

(I don't really know what to do with my friend now, i'll try with my old ram but i guess it won't boot. Maybe he won't mind running at 2133...)

Thanks all! I'm a happy gamer again.

Yeah, identically branded RAM is similarly specced, but it's not actually identical. As with CPUs, there's only so accurate fabrication can be, so this is gotten around by a process of binning and testing.

Just to be very simple and broad, a company selling RAM doesn't really have a whole bunch of different products the way, say, a car company does. Toyota sells a full-size car they call an Avalon, a mid-size Camry, and a compact Corolla. But they seek out to manufacture these specific models; they intend to max X number of Avalons and Y number of Camrys and Z number of Corollas.

But Intel can't do that with CPUs nor can Samsung or Micron do it with RAM. The tolerances are so fine that semiconductor fabrication can't really make functionally identical products. They have to settle for making the best that they can, and then testing each part to see what standards it meets. Again, to oversimplify a bit, Ryzen CPUs all start out as 5950X CPUs, but only the ones that meet certain standards actually become 5950X CPUs. Some only meet the standard for selling it as a 5900X. Some 5800X or 5600X or simply not at all. Now, this binning can also be done voluntarily, purposely classifying a CPU as lower in order to have enough to meet the demands of market segmentation.

 

[kerberos_20]

that binnig process doesnt always apply, sometimes when they have big supply of good bins while low supply on low bins, they will sell it as weaker edition, to keep money flow

as for ram compatibilities when mixing "identical" ram with different production dates, they may appear same, but chip ICs migh be different (one produced with samsung another with micron chips), while they may work standalone, they might not work together, as subtimings (which mainboard trains during first boot) might be different for both of them, they may also do a PCB revision change, which will affect subtimings aswell, think there are 4 pcb versions for ddr4
you coul try to mix it, like 2 same sticks in channel A and another pair in channel B, some mainboards are able to have separate ram settings for each channel

 

[Bob.B]

Thanks for the tips. I have never modified my BIOS in this way so it was rather hard to find did some tests but it didn't boot. Maybe it's just me, i didn't really knew what i was doing



I thought it wouldn't matter... But it did!
My RAM was produced 04/2018 the RAM i now bought has two sticks from 07/2019 and two from 10/2020.

I took my old ram out and replaced it with the new ones and everything seems to work perfectly now. running at 3200Mhz!
The 4 sticks of the Ram i bought doesn't seem to be from the same kit, but sometimes you just have to get lucky i guess?

(I don't really know what to do with my friend now, i'll try with my old ram but i guess it won't boot. Maybe he won't mind running at 2133...)

Thanks all! I'm a happy gamer again.

Mixing ram is a coin flip if it will work or not.
I run 2 different brands of ram and it works fine.
You tried different sticks and it did not work.
Perhaps your old ram will work with your friends ram or not.

 

[Karadjgne]

Best bet, since the ram is the same, call your friend and swap your existing ram for the 2 sticks you gave him, that way you get the full original kit back.