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May 22 (Reuters) - Nvidia forecast second-quarter revenue above estimates on Wednesday and announced a ten-for-one forward stock split, impressing investors who have already tripled the chipmaker's market value in the past year on AI optimism.

The Santa Clara, California-based company's shares climbed 4% after the bell. The AI poster child's shares have risen more than 90% so far this year.

Demand for Nvidia's chips stands unparalleled as enterprises spend billions to procure advanced semiconductors to power data centers capable of processing complex AI tasks.

Alphabet, Microsoft, Amazon and other technology companies have competed for a limited supply of Nvidia's high-end chips as they race to dominate AI computing.

Nvidia's contract chipmaker, Taiwan Semiconductor Manufacturing, has also been working to increase its advanced packaging capacity, a key supply chain constraint for the processors.

The Taiwanese company said in April it expects to more than double its advanced packaging capacity this year.

The company forecast second-quarter revenue of $28 billion, plus or minus 2%. Analysts on average were expecting revenue of $26.66 billion, according to LSEG data.

Nvidia reported first-quarter revenue of $26.04 billion, beatingestimates of $24.65 billion.

(Reporting by Arsheeya Bajwa in Bengaluru; Editing by Arun Koyyur)