HONG KONG--Nvidia Corp. has begun offering an alternative to a high-end chip hit with U.S. export restrictions to customers in China, after the new rules threatened to cost the American company hundreds of millions of dollars in lost revenue. Nvidia said the new graphics-processing chip, branded the A800, meets U.S. restrictions on chips that can be exported to China under new rules rolled out last month. The chip went into production in the third quarter, the company said. The A800 replaces the A100, a chip widely used in servers and artificial-intelligence applications by China's tech giants including Alibaba Group Holding Ltd., Tencent Holdings Ltd. and Baidu Inc. According to a memo Nvidia sent to its channel distributors last Thursday, the A800 has the same computational performance but a narrower interconnect bandwidth, the capacity of a chip to send and receive data from other chips, crucial for training large-scale AI models or building supercomputers.