What motherboard do you have? Unless it's an exceedingly low budget board, most of them will still have a couple fan headers (other than the CPU header).
Also, when using a splitter you can still control the fan; just all at once (so if you have three fans plugged into a fan header splitter and they are all 4 pin fans, you can still tell your motherboard what fan curve to use and it will apply it to all those fans).
usually I recommend up to 3 fans on one header, assuming you get a splitter without additional power.
