F5F Stay Refreshed Hardware Desktop Question about AM5 ram speed sweetspot

Question about AM5 ram speed sweetspot

Question about AM5 ram speed sweetspot

M
McBroke
Member
168
12-10-2021, 05:27 AM
#1
Some believe the optimal point for AM5 is DDR5 6000 since it aligns with UCLK and FCLK for minimal delay. If you switch to DDR5 6200 with MCLK set to UCLK and FCLK at 2067, would everything stay synchronized and maintain low latency?
M
McBroke
12-10-2021, 05:27 AM #1

Some believe the optimal point for AM5 is DDR5 6000 since it aligns with UCLK and FCLK for minimal delay. If you switch to DDR5 6200 with MCLK set to UCLK and FCLK at 2067, would everything stay synchronized and maintain low latency?

M
Mottcru2
Junior Member
48
12-28-2021, 10:47 AM
#2
6000 cl30 usually serves as the default choice because it’s straightforward and simple, provided you’re using a motherboard that has been verified by the Qualified Vendor list (QVL) to be compatible. Many enthusiasts have spent considerable time adjusting RAM timings and speeds, achieving solid improvements—but this requires a significant investment of effort and thorough stability testing. Unless you’re experienced, I’d advise against anything beyond enabling EXPO.
M
Mottcru2
12-28-2021, 10:47 AM #2

6000 cl30 usually serves as the default choice because it’s straightforward and simple, provided you’re using a motherboard that has been verified by the Qualified Vendor list (QVL) to be compatible. Many enthusiasts have spent considerable time adjusting RAM timings and speeds, achieving solid improvements—but this requires a significant investment of effort and thorough stability testing. Unless you’re experienced, I’d advise against anything beyond enabling EXPO.

J
jopehe
Junior Member
29
12-28-2021, 11:49 AM
#3
Yes, you don't have to lock the FCLK. It stays fixed on the Ryzen 7000, meaning a 2200MHz clock is always quicker than 2067MHz, for example. I'd only consider the higher speed if you also adjust sub-timings, since the frequency isn't that impactful compared to those settings. Think of the FCLK as a memory timing reference and tune it last.
J
jopehe
12-28-2021, 11:49 AM #3

Yes, you don't have to lock the FCLK. It stays fixed on the Ryzen 7000, meaning a 2200MHz clock is always quicker than 2067MHz, for example. I'd only consider the higher speed if you also adjust sub-timings, since the frequency isn't that impactful compared to those settings. Think of the FCLK as a memory timing reference and tune it last.

P
PvPking_04
Junior Member
4
01-02-2022, 05:14 PM
#4
I've already adjusted the sub-timings and confirmed stability with DDR5 6200 / 3100 UCLK / 2000 FCLK. Running at DDR5 6000 would eliminate any latency issues.
P
PvPking_04
01-02-2022, 05:14 PM #4

I've already adjusted the sub-timings and confirmed stability with DDR5 6200 / 3100 UCLK / 2000 FCLK. Running at DDR5 6000 would eliminate any latency issues.

G
Gabi_69
Junior Member
41
01-04-2022, 04:57 PM
#5
On Zen4 you might not get any of that, but Zen5 should perform a bit better
G
Gabi_69
01-04-2022, 04:57 PM #5

On Zen4 you might not get any of that, but Zen5 should perform a bit better

N
Nani100
Member
213
01-12-2022, 07:48 AM
#6
This behavior only occurs when values exceed 6000, causing it to switch to 2:1 mode. Adjusting manually to 1:1 mode without instability results in no latency cost. I’d increase the FCLK slightly, likely to 2100MHz, which should be compatible with most devices. Stress testing the FCLK is tricky due to its error patterns—systems often fail only after severe instability, making background music a practical test. Playing music while running Y-Cruncher or Linpack (heavy on core/memory) helps detect subtle issues.
N
Nani100
01-12-2022, 07:48 AM #6

This behavior only occurs when values exceed 6000, causing it to switch to 2:1 mode. Adjusting manually to 1:1 mode without instability results in no latency cost. I’d increase the FCLK slightly, likely to 2100MHz, which should be compatible with most devices. Stress testing the FCLK is tricky due to its error patterns—systems often fail only after severe instability, making background music a practical test. Playing music while running Y-Cruncher or Linpack (heavy on core/memory) helps detect subtle issues.