CPU Overheating After Replacing Fan on Predator Helios Neo 16 (PHN16-71) — Need Help Confirming Root Cause

Hello Acer Community,

I’m following up on my previous post about the fan issue on my Acer Predator Helios Neo 16 (PHN16-71, i7-13700HX, RTX 4050).

🧩 Background

Some months ago, my left-side fan (GPU fan) started making noise and occasionally stopped spinning unless I tilted the laptop.

Eventually, it stopped working entirely. At that time, I posted here to identify the correct replacement fan.

Later, I purchased a pair of FCN Brushless fans (CPU + GPU) but only replaced the CPU-side fan because the GPU fan was still working properly.

Original and Replacement Details

Component	Original Fan	Replacement Fan
Model	SUNON EG75091S1-C112-S9A	FCN DC Brushless
Rating	12V – 9.6W	12V – same rating
Fitment	Perfect match (connector, screws, size)	Perfect
Foam Seal	✅ Present	❌ Missing

Both fans spin up fine, and RPM readings match — around 6000+ RPM at max speed (Turbo mode).

However, after the replacement, my CPU temperatures became abnormally high.

🔥 Current Issue: CPU Overheating

After replacing the CPU fan, my laptop now shows the following behavior:

State	CPU Temp	GPU Temp	Fan Speed	Notes
Idle / light use	55–60 °C	45–50 °C	~3100 RPM	Normal
Cinebench R23 / Gaming	99–100 °C	55–60 °C	6000 RPM	CPU instantly spikes to max
Post-load cooldown	53–56 °C	45–50 °C	~3800 RPM	Cools quickly

Airflow from both vents is strong, and both fans appear to operate normally.

The GPU cooling is perfect, but the CPU overheats rapidly even with full fan speed.

🧰 Troubleshooting Done

✅ System fully cleaned — no dust, vents clear

✅ Both fans run fine (verified via PredatorSense & HWiNFO64)

✅ No BIOS throttling or EC error

✅ Heatsink screws tightened properly

⚠️ New fan missing the black foam sealing strip from the original SUNON unit

⚠️ CPU temperature spikes from 60 °C → 99 °C in just a few seconds under load

📊 Cinebench + HWiNFO64 Test Results

I ran a full Cinebench R23 multi-core stress test while logging data in HWiNFO64.

Below are key screenshots from different phases of the test:

🟢 1️⃣ Idle / Before Cinebench

CPU: ~57 °C | GPU: ~47 °C | Fans: ~3100 RPM

(Normal idle behavior)

🟠 2️⃣ Early Load (Cinebench started)

CPU: 99–100 °C instantly | GPU: ~55 °C | Fans still at 2700 RPM

(Rapid thermal spike before fans fully ramped up)

🔴 3️⃣ Full Load

CPU: 99–100 °C | GPU: 60 °C | Fans: ~6020 RPM

(Fans at full speed, but CPU remains at TJmax)

🟡 4️⃣ Mid-Test (Stabilized)

CPU: 85 °C | GPU: 57 °C | Fans: ~6000 RPM

(Temperature stabilizes slightly after full fan ramp-up)

🔵 5️⃣ Post-Test (Cooldown phase)

CPU: ~53 °C | GPU: ~50 °C | Fans: ~3800 RPM

(System cools down normally afterward)

🧠 My Analysis

Based on the Cinebench behavior and data:

Airflow and fan operation are perfect.
GPU cooling is normal, confirming that airflow and heatsink pipes are not blocked.
The CPU, however, spikes to 100 °C far too quickly, even when fans are at full speed.

This clearly points to a thermal interface issue, either:

Dried or cracked thermal paste (possibly caused by previous vibration from the failed fan bearing), or
Slightly uneven heatsink contact pressure, or
Missing foam air seal, reducing pressure through CPU heatsink fins.

🔍 Questions for Acer Support / Community

Does the Predator Helios Neo 16 (PHN16-71) with i7-13700HX ship with liquid metal on the CPU (as some teardown videos suggest)?
Can the missing foam seal on the new FCN fan significantly affect CPU heat dissipation or airflow direction?
Would Acer recommend repasting (and if yes, using standard thermal paste or liquid metal)?
Can Acer Service Centers perform liquid metal repasting safely for this model?
What are the official part numbers for the CPU and GPU fans for PHN16-71, so I can confirm full compatibility with my FCN replacements?
Are there any BIOS or EC updates related to fan curve or thermal performance for this model?

💡 Additional Details

PredatorSense shows no fan or performance errors.
Laptop always used on Turbo Mode during gaming.
Micron 3400 1TB SSD recently installed (replaced Kingston 2TB).
GPU fan still original (SUNON) and performing perfectly.

🧊Summary

✅ Both fans spin normally

✅ Airflow and venting strong

✅ GPU temps normal

⚠️ CPU instantly hits 100 °C under load

⚠️ Missing foam seal on new fan

⚠️ Likely degraded thermal paste or uneven heatsink contact

I’d really appreciate Acer’s confirmation on whether this issue is related to:

The missing foam seal (air pressure leak), or
Needing a thermal paste/liquid metal reapplication.

If anyone from the community has done a successful repaste or fan replacement on this same model (PHN16-71, i7-13700HX), please share your experience and temperatures afterward.