Overclocking Rome Memory?

[EagerToLearn]

Hello,

has anyone sucessfully overclocked a 2666 MHz or 2933 MHz memory to 3200 MHz on the Rome plattform?

Regards
Michael

 

[efschu3]

If you can wait some weeks until my hardware arrives, I can test for you. But as the IF clocks to 1466 you'd get best performance with 2933 RAM.

 

[EagerToLearn]

The best of the two or better than native 3200 MHz?

 

[efschu3]

In 99% of applications it's better to have the lower latency by running RAM and IF synchron. If you run RAM on 3200MHz it's asychron to IF and you'd probably have a lil higher bandwidth but increased latency.

 

[EagerToLearn]

Thank you very much, that was really helpful information

 

[EagerToLearn]

Since there a lot of posts in the overclocking thread, I was wondering if anyone has tried it?

I am asking, because 2666 seems to be a lot cheaper than 2933 and if I can simply overclock the former, there is no need to buy the latter...

 

[efschu3]

I would directly ask one of the ES/QS Rome owner. Probably they will answer you faster then waiting them here to join our discussion ;-)

 

[111alan]

In fact you can oc the 2666 dram all the way to 3200 if the chips can handle. All server motherboards I used can overclock dram to cpu's support limit. But be aware that not all chips can run stable at high frequency.

Also 2133 and 2400 kits seems to be incompatible on Rome platform, not sure if it's an isolated bios issue though.

 

[efschu3]

Thanks for the OC hint.

But the stuff about 2133/2400 seems not to be true for all configurations:

Not true. I use an Epyc Rome 7282 with four 2133 dimms. They are not even in the QVL (asrock), **but** the QVL explicitly mentions 2133mhz rdimms.

@111alan
Which Board, CPU and memory are you using - you sure your 2133/2400 were rdimm and not udimm (which does definetly not work)

 

[efschu3]

I take my previous statement back for PC-2133 ram.

It does work with ROME, I just tried with a Rome ES and H11SSL-i board.

So both 2400 and 2133 work with ROME ES

 

[bayleyw]

Can confirm, my H11SSL boots using DDR4-2400 ECC RDIMM's that are not on the QVL and there are settings available in the BIOS to set the RAM clocks, though I haven't tried to overclock the RAM yet. I'm not optimistic about overclocking the RAM without voltage tweaks though, DDR4 is binned pretty well these days.

 

[efschu3]

Well it is binned pretty well for sticks with clocks beyond 3GHz, for those clock rates we are talking about (ie. 2933) - almost all should do this w/o increasing RAM voltage. But sure, as always it's silicon lottery.