Like those (molex)? Your PSU should have those. Unless new PSU's don't anymore, I've been out of the loop for a few years. If that is the case, there are some adapters that will go from the fan pin outs on the motherboard to those.
@verity25 Keep in mind, should you decide to use the molex type connectors, your fans will always be running at 100%.
Oncer uppon a time, we had both floppy (3 1/2", and optical (5 1/4") drive bays on the front panel of our cases. These could have been employed as spaces for fan controllers. No such luck nowadays.
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Note that under the "specs" tab, it does have provisions for molex connectors. These are listed as, "peripheral",
This page explains the difference between 3 & 4 pin (small) fan connectors on the motherboard: