Activist hedge fund Starboard Value recently tapped a familiar ally in hopes of boosting the shares of two of its biggest investments: Marvell Technology (MRVL) and Yahoo! (YHOO) .

Starboard, which holds a 6.5% stake in semiconductor producer Marvell and a 2% stake in Yahoo!, seated industry veteran Rick Hill to the boards of both companies within weeks of each other -- a maneuver that's previously paid dividends for the activist fund.

And given Hill's strong track record of boosting tech company share prices, Real Money's Jim Cramer has said that Hill at the board of either company signals a strong time to buy.

"If Rick Hill gets on, then you're going to buy the stock -- period," Cramer told TheStreet in a recent interview, noting Hill's ability to guide former tech company Novellus Systems as chairman from 1996 until its sale to Lam Research in 2012 for $3 billion. Hill subsequently ascended the ranks of Tessera Technologies (TSRA) , from board member in 2012 to chairman in 2013. Tessera shares are up 81% since he first signed on, as of closing trading levels Thursday.

Hill's primary objective at Marvell will be to settle a probe into the firm's accounting, since irregularities in the company's bookkeeping caused the chipmaker to delay the filing of its annual 10-K statement. And resolving the issue will be paramount to moving the company forward, and a Nasdaq board officially gave Marvell this week a postponement until September to put its accounting statements in order to avoid being delisted from the exchange.

Starboard helped to foist Hill onto Yahoo!'s board on April 27, along with three other new board members, including Starboard CEO Jeffrey Smith. Yahoo! shares have been pressured as rising costs have begun to cut sharply into the Web giant's earnings over the last several quarters. Shares have declined 10% more than the past 12 months.

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.