Front fan on case not working

JoshKing2105

Active member
Got my pc at the start of August and everything has been fine, until last week where when I turn my pc on the bottom fan on my case is struggling to spin, goes slow, speeds up and repeats for up to 5 minutes before it then carries on normally. It’s quite loud when it does it and I’m just wondering what I could do to fix it ?
 
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