Is using faster RAM different from overclocking the processor?
Is using faster RAM different from overclocking the processor?
I was recommended to add 3600 ram instead of 3200 on a Threadripper 3960x to reduce latency, but is this considered overclocking or would it require forcing it rather than adjusting voltage settings? Can I overclock with 3200 ram in this setup? Should I use both processors and higher-speed RAM together? Does faster RAM lead to increased clock speeds? What’s the relationship between these factors?
Anything above DDR4-2133MHz is considered an overclock, so you're boosting the RAM speed to reach DDR4-3200 or 3600MHz.
The IMC will handle your overclocks, of course.
No, you're not.
It's an overclock on the RAM and the corresponding memory controller.
It might be (specifically for Ryzen 3000 CPUs) that the 2133 specification represents the official maximum clock speed for DDR4 memory to achieve certification. While manufacturers aim for higher rates, the actual DIMM chips used in kits are selected based on binning processes to ensure compatibility with faster speeds.
Overclocking carries its own risks. To address your inquiry, the answer is yes and no. It differs from simply increasing RAM speed; you must also boost the processor's Infinity Fabric to unlock the full capability of RAM overclocking on Ryzen chips. This stands out compared to Intel processors that rely on a monolithic design.
On systems with Ryzen, it’s important to harmonize the Infinity Fabric clock with the RAM clock. (Values for RAM speed are often paired with their doubled frequency, making it seem like a 1:2 ratio.) For instance, if you aim for a 3600 MHz RAM, use an Infinity Fabric clock of 1800 to achieve optimal results.
Using an Infinity Fabric clock of 1600 with a 3200 MHz RAM is effective, but a 1666 clock paired with 3200 MHz RAM will be slower—even if the 1800 clock is slower. Keeping the Infinity Fabric below 1600 can also hinder performance.
Additionally, keep in mind that various applications or games may require different RAM clock rates relative to CPU speed. The ideal balance often lies around an Infinity Fabric of 1800 with a RAM speed of 3600 and a CL16 setting. Some suggest a sweet spot at 3733 MHz RAM with an Infinity Fabric of 1866, though the cost difference for such precision is significant.
Increasing speed inevitably raises heat in RAM and CPU (especially with Infinity Fabric), so using a DRAM calculator can help fine-tune timing. For those seeking top performance, a 3200 MHz RAM with CL16 is recommended for the best results.
Good RAM plays a significant role for Ryzen processors. This assessment will offer some assistance.
The key challenge with RAM overclocking lies in maintaining the mclock, uclock, and fclock at equal ratios.
When memory speeds exceed 3600MHz (mclock surpassing 1800MHz), the fclock is limited to 1800MHz and the uclock adopts a 1:2 ratio relative to mclock. Activating a 2:1 setting pushes the boundaries of clock domains, introducing a latency penalty of roughly 9ns. This can be mitigated by adding more memory clocks, increasing CPU speeds, or making timing adjustments.
In essence, 2:1 mode reduces performance somewhat, but it remains fixable elsewhere.
It’s still possible to push fclock above 1800MHz, though a strict limit appears around 1917MHz. This explains why many systems settle for IF1900 and cap RAM usage at 3800.
To achieve the best results, tightening the timings of high-quality Samsung B-Die RAM is recommended.
If you happen to own Samsung B-Die kits rated CL16 3600, they can be overclocked to DDR4 3800 with tighter timings (CL14 at 1.5V). This explains why most overclocker setups aim for DDR4 3600 CL16.
If a stable IF1900 isn’t achievable, consider targeting IF1800 with DDR4 3600.
DDR4 3800 CL14 kits are costly but suitable for casual overclockers with limited time for research.
A dedicated enthusiast will seek the optimal CPU and RAM, then resell the rest on platforms like eBay or build systems for clients.
4174MHz 12-12-12-28-1T on 2x8GB Patriot Viper Steel 4400C19
Operating at 2 volts for the DRAM. Using the same setup with DDR4 3800 and 2 volts would allow a 12kHz time spy CPU, provided all cores run at 4.4-4.5GHz. Avoid running 2 volts continuously on the B-Die chip.
Gigabyte Ryzen RAM overclocking
RAM overclocking: 2x8GB Patriot Viper Steel 3866 CL18 (Hynix ICs) on MSI X570 Godlike with 3700X
Performance outcomes: Patriot Viper Steel 3866 CL18 on Asrock X570 Taichi with 3700X