Neither depend on a voip provider - both depend on using T38 to whatever endpoint you have - be it a voip provider or media gateway like a Patton or what not. Your gateway just has to support T38.
To install the 3cx driver, basically download it and install it. in your management console, click "Link" then "Outbound Fax Server." It will ask you for the PBX ip address on install.
If it doesn't work for you - you're gonna have to seek help elsewhere (ie with someone else on this forum) - I have yet to get it to work - hence why I used the T38FaxVoip... which works WONDERFULLY with 3cx.