Question Bios won't post with advertised ram speeds

[Illwamh]

Hi all,

Recently completed a long overdue new pc build. Specs below. However I'm having issues with the ram/mb and getting the ram to the advertised speeds.

My ram is rated at 3200mhz. I can run them at default speed of 2133 without problem with a stable system. I can run them at xmp profile 1 of 2933 without issue with a stable system, however I can't run the pair at anything above this value. If I try, I get a blank display and bios doesn't post (I'm guessing - I have no beeper). I have to remove a stick to get my mb to detect a change and reset to defaults.

I can however run either stick in the preferred slot at 3200 as long as they are not paired. This is via xmp profile 2 which works fine.

I have also tried manually setting the settings as per my ram sticker. I have played with the voltages etc, but as soon as I go above 2933 with 2 sticks I cannot post. I have also tried manually setting each and every setting as recommended by ryzen dram calculator without any joy. Bios is also fully up to date at version 13 by the way.

So I guess I am seeking some help on which of the below is most likely, and how I should proceed.

A) - 2933 ain't bad and I won't notice a difference. Mb likely won't get any higher with this ram paired anyway. (bit annoying as it's a qvl part and I would have bought cheaper lower spec ram)

B) - As above but it likely should work, I just lost the lottery. Don't worry about it.

C) - ram should be rma'd (probably needs more diagnosis. I'm running memtest on the second stick at 3200 now, first reported no errors.

D) - mb should be rma'd (this is my only ddr4 mb so I can't test in another mb. It's just odd that each stick works individually at full speed. I've heard about necessary slow downs with 4 sticks, but never 2?)

E) - I'm a monumental idiot and have overlooked something (quite possible haha!)

Any help would be much appreciated.

Specs
Ryzen 2600
Msi b450 gaming pro carbon
Corsair vengeance lpx - cmk32gx4m2b3200c16 (2 x 16gb sticks)
Gtx 1060

 

[kanewolf]

Verify that you have the latest BIOS for the B450. RAM stability is something that has to be baked into the BIOS. BUT, it may be that 2933 is all that even the motherboard manufacturer got.

 

[Illwamh]

Hi Kanewolf

Thanks for taking the time on this to help me. As I said above, I have already verified my bios is running the latest version. Actually typo'd above, my bios is on the latest version 140.

I understand what you are saying and maybe I just need to accept 2933. However it just seems odd to me that both sticks work solo at 3200. To me that implies I should be able to get it to work across both sticks? Unless my understanding is wrong.

The ram is also on the qvl list for my motherboard (obviously listed at 3200). Again I would expect that to mean it should work at the rated speeds (rather than just work at all)?

 

[kanewolf]

Ryzen and RAM are fickle partners. The typical recommendation is to try .05 or so of extra voltage to see if that makes it stable. Or you could RMA to the manufacturer and wait with no RAM ...

 

[Illwamh]

I'm going to spend a little more time playing with voltages etc. I bumped it to 1.4v and still couldn't get it to post though so not holding out much hope.

If I was going to rma something though, is it more likely the mb at fault? If both sticks work at 3200 solo?

 

[kanewolf]

I'm going to spend a little more time playing with voltages etc. I bumped it to 1.4v and still couldn't get it to post though so not holding out much hope.

If I was going to rma something though, is it more likely the mb at fault? If both sticks work at 3200 solo?

I am not a person that pushes the envelope for that last 5% ... I would be happy with a system that was stable at 2933. The performance changes above that are very minimal.