San Francisco ? Sun Microsystems Inc. shares soared almost 80 percent Wednesday on a report that the company is in merger talks with IBM Corp., which may pay $6.5 billion in cash to acquire the struggling high-tech giant.

If the deal is finalized at that price, it would be the largest purchase ever for Armonk, N.Y.-based IBM, whose last big acquisition was the $5 billion purchase of Canadian software maker Cognos in 2007.

The Wall Street Journal reported Wednesday that including the $1.4 billion in cash on Sun’s balance sheet, the total value of the deal would be about $8 billion or some $10 to $11 a share.

IBM is interested in buying the struggling computer server and software maker as a way to put hardware back at the core of Big Blue’s operations and bolster its computer-server business, according to the article.