Waiting for my liquid cooler to arrive still. Unfortunately Arctic confirmed it doesn't include the AM4 bracket, which will be available mid March. I also emailed Raijintek about the Triton 360, and that will have the AM4 bracket in 7 to 10 days.
In the meantime, I found out the Be Quiet! Pure Rock I have mounted on my i7-6700K is compatible already, so I put a Deepcool TF120 on it and put it on the 1700X with some Noctua NT-H1. Unfortunately it doesn't seem to have made much a difference, as I'm still getting mid 70s at load (3.6GHz, all cores) with AIDA64 stability test.
Oh well, I guess I'll wait for liquid cooler to further OC. I think I'd need a more massive heatsink if I wanted to do air at ~4GHz and maintain cool temps.