I have the stock fans that came with my H440. I was hearing a buzzing noise coming from my computer so I turned it off, and then on again and it stopped. So I decided I'd look inside, so I turned it off once again but accidentally pressed the power button twice (don't ask how). So when I took off the filter, it turned on again and I wasn't careful so a single fan blade broke off of one of the three. I cleaned the filter, came back, and noticed the missing fan blade. The broken piece was on the floor. So I wanted to ask how urgent would replacing that fan be? And which fan would fit in a h440? Thanks!