OpenAI advances talks to lease a proposed 10-gigawatt data center campus on federal land in southern Ohio, where SoftBank's SB Energy would construct the facility on Department of Energy property under a 20-year agreement with payments commencing at operations. The first phase targets 2028 while Nvidia $NVDA supplies hardware plus financial guarantees covering both the lease and SB Energy financing, extending Nvidia financial guarantees for hyperscale data centers and aligning with SoftBank SB Energy DOE land projects history amid rising AI infrastructure demand.