The9 (NCTY) shares gain 6.8% premarket after signing three Chia ((XCH)) cryptocurrency mining machine purchase and cloud service leasing agreements with three unrelated vendors, with the total contract sum of more than $5.7M.Upon the executions of these agreements, the company will obtain approx. 130 Pebibytes Netspace, and to join the ecological construction of Chia cryptocurrency, also known as the "Green Bitcoin Alternative". Chia was created by Bram Cohen, the inventor of BitTorrent and was developed through Chialisp. Unlike Bitcoin, which uses proof of work, Chia uses proof of space and time consensus algorithm.Remaining space on the hard disk can be used to verify transactions without the need of consuming a lot of computing power and electricity to maintain the Chia network. Therefore Chia is considered to be a more green and environmentally friendly blockchain technology.The9 had previously invested in Bitcoin and Filecoin mining machines.