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Cerberus-X late 2024 : Cooling the AMD Ryzen 7 9800X3D (19th December 2024)
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Let’s start with the harsh facts : My Noctua C14S, paired with 2 Noctua NF-A25x14G2 was not able to cool the AMD Ryzen 7 9800X3D @stock settings during AVX512 workload (IBT2.54 with a maximum 154.34W used) without thermal throttling!!!
The AMD Ryzen 7 9800X3D is given for a base TDP of 120W but it can boost till 160W.
Based on my former experience I was expecting my Noctua C14S to be effective till 170W but based on a monolithic & central design processor, like my Intel Core i5 12600K overclocked @5.2Ghz. But facts are clear, Zen 5 (like Zen 4) is based on very small chiplets, significantly harder to cool efficiently!
On top of that, I noticed major power peaks on the R7 9800X3D during gaming sessions. “Dragon Age: the Veilguard” can consume between 80W-120W during standard gameplay, but sometimes this is exceeding this amount significantly (~140W-150W). Of course I’m excluding shader compilation as it is also a power hungry task. Those power peaks were leading to distracting & irritating fan noise…ie not acceptable from my point of view.
That is where my quest to cool & tame the AMD Ryzen 7 9800X3D started..
I would target two main objectives :
- Explore alternative CPU coolers
- Undervolt / underclock the AMD R7 9800X3D
Best CPU Cooler (Cerberus-X)
I thought of 2 main competitors (both 120mm Tower style) of my beloved Noctua C14S inside the Cerberus-X :
- Thermalright peerless assassin 120 mini
- Noctua NH-D12L
Finally I decided to keep only the Noctua NH-D12L as “Thermalright peerless assassin 120 mini” fan is pretty mediocre in terms of noise and difficult to replace (due to fan clip)
Here are common parts :
- Thermal paste : Arctic MX-6
- Noctua Offset mounting hardware : NM-AMB13 (C14S) & NM-AMB14 (D12L)
Let’s compare the 2 cooling setups :
- Noctua C14S :
- Orientation : Vertical (Heatpipes are towards top of the case)
- Fresh Air Intake : From the top of the case
- Hot Air Exhaust : Towards the side of the case (with NM-AMB13, the Noctua C14S is perfectly aligned with the side panel aeration)
- CPU Cooler Fans : 2xNoctua NF-A14x25G2 placed as exhaust (perfect to exhaust all the hot air coming from the GPU)
- Other Fans : None
- Final setup look :
- Noctua D12L :
- Orientation : Horizontal (I tested Vertical orientation, but it was requiring too much speed from the 2xbottom intake fans to cross the GPU)
- Fresh Air Intake : From the vented side of the case
- Hot Air Exhaust : Towards rear & top of the case
- CPU Cooler Fans : 1xNoctua NF-A12x25R
- Other Fans : 1xNoctua NFA9-25 (Rear) + 1xNoctua NF12x25 (Top)
- Final setup look :
So is there any clear winner?
Well...well...here is a comparison from IBT 2.54 Very High profile (Intel Burn Test), assuming, similar peak power consumption :
Short answer between the Noctua D12L and the Noctua C14S, inside Cerberus-X, on a Ryzen 7 9800X3D (~155W TDP) :
- Pure Cooling performance : very similar on either CPU & GPU (RTX 4080 FE was also very similar)
- Cooling/Noise ratio : Advantage for the Noctua D12L as 140mm tends to be too noisy for me above 1000 rpm
At least, I've my own opinion on the debate between the 2 CPU coolers within the Cerberus-X. It could be important as I read some rather too optimistic review on reddit stating some 15-20°C advantage for the D12L over the Noctua C14S.
Here are some gameplays video using both CPU cooler, at stock settings :
- Noctua C14S :
- Noctua D12L :
Undervolting/Underclocking the AMD R7 9800X3D
Basically this step represents most of the time I've spent tweaking my setup. However I will spare you the boring approach of trials/errors..
I will try to sum-up what I've experienced :
- The most limiting factor for undervolting : Gaming. Basically undervolting PBO Curve Optimizer -30 was working fine with IBT 2.54 & Cinebench, but drivers were crashing while gaming.
- Best undervolting setup was using PBO Curve Shaper (new feature introduced with Zen 5), instead of Curve Optimizer
- Best undervolting setup : PBO Curve Shaper :
- Min Frequencies : -30
- Low Frequencies : -30
- Med Frequencies : -30 (Max Threads performance, like Cinebench)
- High Frequencies : -10 (Gaming)
- Max Frequencies : -10
- Despite PBO undervolting, I'll still experienced audible power peaks while gaming, thus I decided to test also underclocking
- I tested 2 ways to underclock :
- MSI Bios : TDP setup with power range
- 120W-160W (Stock)
- 95W-128W (no gaming performance loss)
- 65W-88W (Gaming performance loss up to 2%, mostly equal)
- AMD PBO / Limit / Manual / PPT : Put Wattage in W (some other MB could be in mW). Tested (& approved) at 95W
- I recommend PBO PPT Limit as I experienced regular stutters while gaming with MSI Bios TDP Setup, especially at 65W-88W TDP
- Overall undervolting & underclocking (TDP limit) is leading to massive efficiency "Performance/Watts" improvements (up to +52%) versus stock parameters
As I was pleased with the overall results of undervolting/unclocking (look at this Cinebench 2024 Multi score at 1303 with a 95W TDP vs 1360 at best with 128W/PBO-Curve Optimizer -15) I decided to test a tiny CPU cooler, suited for mini ITX builds, the ID-Cooling IS-47-XT (47mm tall, 92mm slim fan, 95W TDP in Theory)
BONUS : ID COOLING IS-47-XT vs AMD R7 9800X3D
Here is the almighty ID Cooling IS-47-XT :
- 2 orientations possible ! (like most of Noctua CPU coolers)
- Good contact pressure
- Feeling as if it is missing something!
- Full setup using Noctua NFA9-14 PWM fan, 2500rpm Max
- Cooling Performance tested with a TDP of 65W-88W (Pass) and 95W-128W (heavy thermal throttle)
- Gaming Performance (TDP 95W-128W) : Very loud and thermal throttle
- Gaming Performance (TDP 65W-88W) : Quieter than the RTX 4080 FE, no thermal throttle!
- Idle noise : While at 65W-88W, the R7 9800X3D was basically quiet (not audible) even I needed to setup idle CPU temperature at 65°C (thermal balance was stable)
This test was not totally innocent as I wanted to test my R7 9800X3D in smaller cases than my Cerberus-X (like my N-ATX v2). Overall I'm impressed by both the ID Cooling IS-47-XT and the AMD R7 9800X3D, even undervolted/underclocked!
The AMD R7 9800X3D is shining by its incredible power efficiency!
I hope you enjoyed this article as much as I did.
More to come...hopefully still this year!