Hewlett-Packard interim chairman Ralph Whitworth is stepping down to focus on his personal health.

Whitworth's resignation is effective Wednesday, July 16, and the board will discuss appointing a new chair at its next meeting. Whitworth became the interim chair in April 2013. He succeeded former chair Ray Lane.

Sources report the computer hardware and services company has been trying desperately to recover from a downturn in PC sales. There were internal shakups within the company during Lane's days as well. At the time he resigned two other directors, John Hammergren and G. Kennedy Thompson, also left with him. Stockholders were unhappy with the company's performance at the time. Chief Executive Officer Leo Apotheker also left the company.

As PC desktop and laptop computers have begun to take somewhat of a backseat to the mobile computing experience, HP has struggled a bit to keep pace. It has made more of a concerted effort, along with other companies, to focus on software and services. The cloud has led to major areas of growth in this arena.

According to another report, Whitworth is also taking a leave from his money management firm, Relational Investors. He is the co-founder and principal of that firm.

The 58-year-old Whitworth joined the board at HP in 2011. The current CEO, Meg Whitman, is facing just as many (if not more) struggles. The company has cut many positions and may cut several thousand more, according to reports.

"Ralph has been a friend and close adviser to me, the HP leadership team and every member of the board for nearly three years," Whitman stated. "He has been a wonderful contributor to our efforts to turn HP around."

Another source reported Whitworth's duties at Relational Investors, the firm he co-founded in 1996, will be assumed by the other co-founder, David Batchelder, as well other senior managers.

Shares of Hewlett-Packard fell less than half a percent to $34.01 around 8 a.m. EST. The company's stock has risen 22 percent this year so far, before the dip.

Whitworth's financial firm Relational Investors buys into companies it considers undervalued, then applies pressure to boards and executives to boost returns for investors, sources say. The company said it will continue to serve its clients' interests.

Also according to sources, Whitworth vowed to push for share buybacks, larger dividends and more investment in research, but that strategy has not played out. The company's spending was down slightly for research and development. Relational, reportedly, has a 1.5 percent stake in HP.