3600 Hz RAM cant get past 3066 Hz

kevman · 19 Sep 2020 at 18:20

Currently running 7700K MSI z270 SLI Plus

I originally had 2 sticks of 8 Gb of Corsair 3200 CL16 ram in the system. I clicked on XMP and she was good to go. Have been running like this since I bought the system.

I wanted to upgrade to 32 Gb of Ram and picked up 2 sticks of 16Gb Crucial Ballistix 3600 CL16. Initially I clicked the XMP and system did not post.

Since then I have been mucking around with the frequencies and voltages and it will only post at 3066 and below. I have tried voltages up to 1.45V. I was able to add the XMP timings but just could not increase the frequency.

Is the Ram just a dud set or is this a symptom of my older board? According to crucial it is 100% compatible but this could just be at stock settings?

pc-guy · 19 Sep 2020 at 19:27

you are mixing rams which is not a good idea. you should be getting another set of the exact same ram as your original corsair rather than going for crucial ballistix. or ditch your old ram and go full set of matched 2x16GB.

you are lucky they can even post and run at 3066MHz

kevman · 19 Sep 2020 at 19:34

pc-guy said:
you are mixing rams which is not a good idea. you should be getting another set of the exact same ram as your original corsair rather than going for crucial ballistix. or ditch your old ram and go full set of matched 2x16GB.

you are lucky they can even post and run at 3066MHz

Sorry - yeah I have completely removed the old 16 Gb (2 sticks) and replaced with 32gb (2 sticks)

pc-guy · 19 Sep 2020 at 23:39

Your board took 3200 MHz before so it should be fine.

you made sure the new sticks are in the same dimm slots as the old ones?

anyway, run some memtest at stock 2400MHz. And run them again at the postable 3066MHz and see what you get. If they can’t do XMP them there may we’ll be something dodgy with it. I got a set of ballistix that were duds on arrival. 3200Mhz returned lots of errors and at 2400MHz no errors. But crucial return policy is a bit crap. They need the ram to be returned and tested and then post out new ones. Best to deal with the retailer. In my case the forest gave me money to buy a new set from they again while waiting for my ram to be returned. So I got new ones next day.

Rroff · 19 Sep 2020 at 23:44

pc-guy said:
Your board took 3200 MHz before so it should be fine.

Different memory chips and/or different amounts of RAM can make a difference to what is possible - 32GB has generally been harder to get higher frequencies stable than 16GB even with the same number of dimms populated.

It is possible the memory controller simply can't handle anything higher with 32GB.

pc-guy · 20 Sep 2020 at 00:03

Rroff said:
Different memory chips and/or different amounts of RAM can make a difference to what is possible - 32GB has generally been harder to get higher frequencies stable than 16GB even with the same number of dimms populated.

It is possible the memory controller simply can't handle anything higher with 32GB.

You might be right there.

is the memory controller on NB or CPU? Anyway when you enable XMP you probably also need to increase NB and CPU bolts etc to get stable clocks

Rroff · 20 Sep 2020 at 00:03

pc-guy said:
You might be right there.

is the memory controller on NB or CPU? Anyway when you enable XMP you probably also need to increase NB and CPU bolts etc to get stable clocks

Most recent CPUs have an IMC - a few setups still have a memory controller on the NB but it is much rarer these days.

On my 4820K the IMC just goes flat nope to anything above about 2000MHz with 32GB regardless of how many slots are used, etc. for it - while 16GB it will do 2400MHz with loose timings or 2133MHz with tight.

pc-guy · 20 Sep 2020 at 00:09

My last chip was a 4770k. So don’t know much about how well kaby lakes can clock in terms of ram speed. I am 2400MHz DDR3 which was considered to be high end for haswell platform. But thinking back, 3200MHz is now a standard frequency. But 4yrs ago it is considered high end. Even 3000MHz is considered v good. So it is possible that there is a hard ceiling with the ram controller.

however it is worth noting that crucial ram has life warranty. So keep that receipt at hand

kevman · 20 Sep 2020 at 08:00

pc-guy said:
anyway, run some memtest at stock 2400MHz. And run them again at the postable 3066MHz and see what you get. If they can’t do XMP them there may we’ll be something dodgy with it. I got a set of ballistix that were duds on arrival. 3200Mhz returned lots of errors and at 2400MHz no errors. But crucial return policy is a bit crap. They need the ram to be returned and tested and then post out new ones. Best to deal with the retailer. In my case the forest gave me money to buy a new set from they again while waiting for my ram to be returned. So I got new ones next day.

Thanks will try this - I still have the old sticks so returning them is not such an issue.

Rroff said:
Different memory chips and/or different amounts of RAM can make a difference to what is possible - 32GB has generally been harder to get higher frequencies stable than 16GB even with the same number of dimms populated.

I did wonder this. I am thinking about upgrading the platform soon. Is there anyway of knowing which boards have a decent mem controller. I noticed that newer boards can cope with overall more RAM e.g. 128 Gb. IS this an indicator of being better able to control the RAM?

pc-guy · 20 Sep 2020 at 08:15

kevman said:
Thanks will try this - I still have the old sticks so returning them is not such an issue.

I did wonder this. I am thinking about upgrading the platform soon. Is there anyway of knowing which boards have a decent mem controller. I noticed that newer boards can cope with overall more RAM e.g. 128 Gb. IS this an indicator of being better able to control the RAM?

Memory controllers are all in ryzen CPUs now.

that’s why you need to yank the vdimm as well as Vsoc and some other voltages to get stable clocks. But 3200MHz is very standard for zen+ and zen2.