My PC has three generic 120 mm intake fans, one rear exhaust fan, and a 360 mm top-mounted liquid-cooling radiator with three powerful 3000 RPM fans exhausting upward through it. Because the radiator fans move much more air than the intake fans, the case likely has fairly strong negative pressure.
How much of a problem is that over the long term compared with positive pressure? Will it noticeably hurt cooling or fan lifespan, or mainly cause more dust to enter through gaps and unfiltered openings? Is there a practical way to bring the case closer to neutral or positive pressure without significantly reducing radiator airflow?
3 Answers
You can also test different layouts, such as mounting the radiator at the front or side as an intake, if your case supports it. Another simple option is to turn the rear exhaust into an intake, but check temperatures rather than assuming more positive pressure is automatically better. A clean filter and sensible fan curves matter more than achieving a specific pressure balance.
If the case has dust filters, slightly positive pressure is usually preferable because most incoming air is forced through those filters. You can try increasing the intake fan speeds, lowering the exhaust or radiator-fan speed when temperatures allow, or adding another intake fan. Keep the radiator exhausting if that gives the best CPU and overall cooling results.
Negative pressure generally will not damage the PC. The main downside is that air gets pulled in through every available gap, including openings that may bypass your dust filters, so the interior can become dirty faster. Cleaning the filters and components more often may be all that is needed.
Related Questions
Lenovo Thinkpad Stuck In Update Loop Install FilterDriverU2_Reload