That tops rival Dell Inc.'s offer Thursday morning of $1.52 billion.
Dell made its first offer for 3Par Inc. on Aug. 16. Hewlett-Packard Co. countered on Monday.
Both companies are interested in 3Par as a way to save money as they bulk up data center operations, which help them deliver software and services to customers over the Internet.
Dell's agreement with 3Par gives Dell time to match competing offers such as the latest from HP.
Dell declined to comment on the new bid.