OK... for EOS utility only USB cable should be enough.
Just be aware, there are some
reports here on forum of excess readout noise (banding) when USB cable is attached.
I never noticed this with my 400D (maybe because banding is higher than average), but I was still using the camera with computer un USB only for framing and focussing (with help of FocusAssist) and after that I would remove the laptop and continue with remote only (for actual images and dark frames).