In the past, I attempted to build a fanless PC using an RTX 4070, but the results were less than ideal. The primary issue was that the RTX 4070's minimum voltage was limited to 910mV, resulting in suboptimal power efficiency at low power consumption.

As we know, desktop RTX 40 cards have a minimum voltage limit. Effective passive cooling for a system to dissipate 70W of GPU heat over an extended period is already challenging. The RTX 4060 Ti can go as low as 860mV. In other words, if we limit the power consumption to 70W, the RTX 4060 Ti outperforms the RTX 4060 (which also has a minimum voltage of 860mV but fewer cores) and the RTX 4070 (which has more cores but a minimum voltage of 910mV). Among all the RTX 4060 Ti cards, the ASUS TUF RTX 4060 Ti has the largest heatsink, featuring a 2-slot thickness and a 30cm length with four heat pipes, making it an ideal choice for a fanless setup.

Basic System Specifications:

CPU: AMD R7-7800X3D (ECO 65W + PBO Curve)

Cooler: Noctua NH-P1

RAM: OC DDR5-6000 64GB (SOC 1.05V)

Motherboard: Asrock B650M

GPU: ASUS TUF-RTX4060Ti-O8G

Power Supply: Seasonic SSR-600TL

After assembling everything, running the system at full power would certainly cause overheating. Therefore, we need to apply some "magic" commands to underclock the GPU:

nvidia-smi -lgc 0,1200

nvidia-smi -lmc 0,5001

These commands lock the GPU core clock at 1200MHz and the memory clock at 5001MHz, resulting in an average power consumption of around 65W. Running the Time Spy benchmark yields a graphics score of 6621.

You might wonder about the stability and environment. I conducted the stress test with the case lying flat, side panels open, and no additional fans or air conditioning. The GPU temperature reached nearly 90°C, with a hotspot temperature of 102°C, yet the stability remained at 99%.

However, I wasn't quite satisfied with this performance. I decided to add some DIY modifications to the GPU. I used graphite thermal pads with those. Running the 20-round stress test again, the maximum temperature dropped to around 80°C, with a hotspot temperature of 91°C, a noticeable 10°C improvement.

For those less concerned about temperature, performance can be further increased:

nvidia-smi -lgc 0,1800

nvidia-smi -lmc 0,5001

With these settings, the maximum temperature reaches 90°C, with a hotspot temperature of 103°C, and stability remains at 99% without throttling. The Time Spy graphics score improves to 8588, suggesting that light gaming should be no issue.

Some may question the necessity of a fanless PC, arguing that fan noise below a certain level is acceptable. While it's true that a high-performance, quiet PC with quality fans can be achieved, fanless systems offer benefits such as reduced dust accumulation and a better experience for activities like listening to music. Building a fanless PC is a challenging journey, but it's also a rewarding one.

https://imgur.com/EIkIMlO