Why does my computer fan keep spinning loudly and how can I reduce the noise?

I totally get why you're concerned about the loud fan noise - it can be really distracting and worrisome when it comes to your hardware's longevity. First, I think it's great that you've already checked the dust filters and ventilation, as those are common culprits behind loud fans. Given your recent GPU upgrade, I'm guessing the new graphics card is probably the main reason for the increased fan activity, especially when you're gaming or running resource-intensive programs.

One thing you could try is checking your GPU's cooling settings - some graphics cards allow you to adjust the fan curve, which can help reduce noise levels. You might need to install a specific software tool from your GPU manufacturer to access these settings. For example, if you have an NVIDIA card, you can use their GeForce Experience software to adjust the fan settings. Additionally, there are some third-party tools like msi afterburner or gpu-z that can help you monitor your GPU's temperature and fan speed.

If adjusting the fan settings doesn't make a significant difference, you might consider looking into a better cooling solution, such as a liquid cooling system or a high-quality air cooler specifically designed for your GPU. These can be more expensive, but they can be really effective in reducing noise levels and keeping your hardware at a safe temperature. I'd also recommend keeping an eye on your system's overall temperature and adjusting your workflow accordingly - if you notice the fan noise increasing, you can try closing some resource-intensive programs or taking a break to let your system cool down.

I hope this helps, and I'm sure you'll be able to find a solution that works for you. If you have any more questions or need further guidance, feel free to ask - I'm here to help. Good luck with tweaking your system, and I hope you can get back to a peaceful and productive workflow soon!