Question Can I put a 3 pin fan into a 4pin slot on my mobo?


By "slot" I presume you mean a standard 4-pin fan header. Yes, you can plug in that way. The physical construction and electrical connections allow that. However, that may NOT allow you to control that fan's speed without a small adjustment in BIOS Setup. The METHOD of controlling a fan's speed used by the header needs to be different for this fan, and most mobos allow you to set this. For new 4-pin fans the header needs to be set to use PWM Mode; for your 3-pin fan it needs to be Voltage Control Mode (aka DC Mode). If you are not familiar with how to access BIOS Setup and do this, post back here the maker and model of your mobo, and we can give you precise instructions.