So my pc setup is a GTX 1070 and an  i7-7700. Since the downfall of many cryptocurrency in the past few months, I have started using nicehash autominer for my graphics card. Now the question is, my cpu lies at barely 5% use throughout the day. So are there any viable cryptocurrency that I can mine using my cpu???

You give us the best incentives to post 
https://bitcointalk.org/index.php?topic=5095785.msg49173712#msg49173712

If you're just starting out, you can check reviews made by other people on that coin to get a basic idea about it. If you're willing to put in the elbow grease, you can check the various features that specific coin offers like privacy or decentralization. You can check how valuable such features are by comparing them to other more popular coins. If the team releasing this coin has been trustworthy and released a few good potential coins then you trust the new coin as well. To be honest, the best coins to invest in are already on various markets top coins list. I would suggest that you invest in these established coins rather than finding very young and newly bud coins to invest in. I might be saying that cause I don't have much of a risk appetite myself