Memory won't run D.O.C.P.

[jhawk2122]

I've had a hell of a time getting my memory stable at the advertised speeds.  I've tried setting it to use D.O.C.P. in the BIOS, including with increased DRAM voltage, but the system won't post.  I've tried using the RAM overclocking calculator and manually setting the timing numbers, but that never works.  The only way that I've gotten close is by manually setting the first five CL timings, and leaving everything else to auto.  This boots, but (1) it's still not as fast as the advertised XMP timings, and (2) I have to run it at 1.4v, which maybe isn't ideal long term?

 

Today I sanity checked that my RAM (G.Skill Ripjaws V) is on my motherboard's QVL, and it looks like there are some slight differences between the Part No.'s.  Is this potentially the problem?  I'd hate to buy another set of memory (I bought in early Jan, so past the time to return), but I may do it if it would make a difference in speed (and long term stability, which is perhaps more important).  Pics of the QVL and Thaiphoon readout for my memory below.  I've highlighted the QVL listing for the closest Part No.. 

 

Thaiphoon read out: F4-3600C16-8GVKC

MB QVL listing: F4-3600C16D-16GVKC

 

Are these sticks different, or just different listing conventions?  Could this be what is causing my inability to simply run D.O.C.P. settings?

 

ROG STRIX B450-I GAMING

Ryzen 5 3600