I'm trying to figure out if moving to a larger GPU, specifically an XFX Merc OC that takes up 3.5 slots, is messing with my CPU cooling. Previously, I had a smaller 9070XT Pulse that only covered 3 slots and I returned it because of performance issues. Currently, my setup includes a Phantom Spirit CPU cooler and three 120mm intake fans. Here's the situation: the distance between the front intake fans and the GPU is about 5 cm. It seems like the bottom fan blows air underneath the GPU, the middle fan directs air right into the GPU, and only the top fan feeds cool air toward the CPU.
Before switching GPUs, my CPU temps were around 43-45°C at idle, but now they're sitting at 48-49°C. During gaming, it used to hit about 55-60°C on average, going up to 65°C in CPU-heavy scenarios. Now, I'm consistently above 60°C while gaming and experiencing highs in the 60s to low 70s for CPU-intensive games. I'm considering changing the thermal paste, but I wonder if this larger GPU has compromised my airflow. Should I look into a bigger case or invest in a liquid cooler? My CPU is a 7800X3D and I'm using a Corsair 4000D case.
1 Answer
The key to your issue is the case you're using. A case with good airflow makes all the difference. For example, in my Fractal Torrent Compact, my CPU temps barely changed with full GPU load compared to idle. However, in cases like the NZXT S340 Elite, I saw a significant CPU temp rise. So even though you've got a larger GPU now, you might be okay if your case is designed for airflow.
I'm using the Corsair 4000D too! With the previous GPU, I noticed it had more space, but this new card is both longer and thicker. I think the close proximity to the front fans (about 5 cm) is what's causing the issue.