EPYC Rome RAM settings for XMR performance

boomheadshot

Member
Mar 20, 2021
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I've got 8 X M393A2K43DB3-CWEGQ sticks and a 2s1404e2vjug5 CPU

Using the EDC bug and @ 2.6 GHz, I get about 40 kh/s, @ 3.0 GHz I get about 44.5 kh/s mining XMR. Don't want to push it higher because the power draw is already quite crazy.

I was curious if it's even worth bothering with tuning the RAM, I specifically bought these sticks because they were 3200 MHz, but then I realized how loose the timings were, so if you divide the frequency by the CAS latency, you get practically the same performance (3200 @ CL22 ≈ 145, while 2400 @ CL17 ≈ 141, so a minimal difference to say the least).

I looked through the BIOS and did indeed see a section where you can tune the timings and subtimings (ASUS KRPA-U16).
Is it even worth it? Or is server memory abysmal at overclocking? Memory tuning on consumer boards has a quite noticeable effect on performance in this certain task (from my testing, it scaled almost linearly if my memory serves me right)
 

Wilhelm

New Member
Aug 1, 2019
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I would also like to know if there is much difference between 3200 vs other slower speeds for my 2 x ZS1406E2VJUG5. I bought 4 x 32GB DDR4-3200AA RDIMM for usd450 last year just to make sure my system was working properly, now I need to buy 12 more sticks and the price is much much higher.
 

boomheadshot

Member
Mar 20, 2021
64
4
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I got 11 x 32 GB 2400 MHz sticks for $67 each (mega lucky, I know), right now I have 10 of them plugged in (was testing the memory, no issues), and it's only doing 32 kh/s @ 2.6 GHz, and with 4 sticks it was like ~36 kh/s (I think it's the extra 2 sticks adding latency on one of the channels), just my guess. I guess there is a difference, but I've seen a lot of peeps on XMRig benchmarks getting decent rates with 2666 sticks, so IDK if it makes a difference.

My new 32 GB sticks aren't on the QVL, IDK if it could make a difference
 

ari2asem

Active Member
Dec 26, 2018
711
130
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The Netherlands, Groningen
my experience with dual socket 7442 (totall of 256 threads) and 16 sticks of 32gb and 3200 mhz

bios setting:
tdp set to 180 watt to keep VRM-temps below 75°C
hashrate is around 71 kh/s. normally i get 81 kh/s. but now is one of my cpu's running at lower speed. maybe i have to renew the cooling paste and blow out the dust inside cpu cooler.

with 8 RAM sticks for dual cpu i get hashrate of 34 kh/s

no cpu overclock
 

boomheadshot

Member
Mar 20, 2021
64
4
8
my experience with dual socket 7442 (totall of 256 threads) and 16 sticks of 32gb and 3200 mhz

bios setting:
tdp set to 180 watt to keep VRM-temps below 75°C
hashrate is around 71 kh/s. normally i get 81 kh/s. but now is one of my cpu's running at lower speed. maybe i have to renew the cooling paste and blow out the dust inside cpu cooler.

with 8 RAM sticks for dual cpu i get hashrate of 34 kh/s

no cpu overclock

34 kh/s with 2 CPU's... IDK, that's just underwhelming. I would try to improve the cooling on the VRM and just crank up the TDP. I've got a fan blowing on it right now, and the chokes are kind of hot, but the VRM seems cooler. Keeping it at 2.6 GHz even though I can do like 3.2 stable because the extra power draw (and heat) aren't worth it.

If you're just doing it in your spare time while the system isn't loading, I get it. But if you want to get a little more back from a system that cost a shitload of money, then I would go for higher frequencies.
 

ari2asem

Active Member
Dec 26, 2018
711
130
43
The Netherlands, Groningen
34 kh/s with 2 CPU's... IDK, that's just underwhelming. I would try to improve the cooling on the VRM and just crank up the TDP. I've got a fan blowing on it right now, and the chokes are kind of hot, but the VRM seems cooler.
34 kh/s is for 4 Ram stick per cpu, thus the half of memory channel.
with 8 Ram stick per cpu (full memory channel) i get 80 kh/s with dual cpu's.

this means that for monero mining it is important to have full memory channel. 8 Ram stick per cpu
 

boomheadshot

Member
Mar 20, 2021
64
4
8
34 kh/s is for 4 Ram stick per cpu, thus the half of memory channel.
with 8 Ram stick per cpu (full memory channel) i get 80 kh/s with dual cpu's.

this means that for monero mining it is important to have full memory channel. 8 Ram stick per cpu
Oooh, now I understand why your hashrate drops when you remove half of the sticks, I forgot that you have only 4 channels per DIMM if your remove half of the sticks.

Just for the record, I removed 2 DIMMs to leave 8 in the board (as per the manual instructions), and what do you know, the hashrate has gone up from 32k to 39.9k, this is on the 2400 MHz CL17 modules. The 3200 MHz CL22 modules, the hashrate was slightly higher than this at about 40.3kh/s