With $17 billion in assets, Microsoft CEO Steve Ballmer tops the list of the wealthiest CEOs in the U.S., according to Wealth-X.

Ballmer has a total wealth of $17 billion and earned $1.3 million in salary and bonus last year, according to Wealth-X, a research firm that focuses on the ultra wealthy market. Most of the top five are from technology companies.

Ballmer has acquired the highest wealth total despite being the lowest paid of the Dow Jones CEOs in 2012. Microsoft trimmed pay for executives last year, citing slower-than-expected growth in its online services division and a $732 million fine for failing to comply with European regulations.

The only woman to be in the top five, Meg Whitman, CEO of Hewlett-Packard, is the second wealthiest CEO with $1.2 billion, according to Wealth-X. She received $15.3 million in compensation last year.

Whitman was brought in from heading eBay to turn around business at Hewlett-Packard. She is one of the technology chief executives who has tied her compensation to the company’s performance.

Stephen J. Hemsley, CEO of UnitedHealth Group, comes in third with $480 million in total assets. He was paid $13.8 million in salary and bonus in 2012.

Fourth on the list is John T. Chambers, with $430 in total assets. He is CEO of Cisco Systems and was paid $11.6 million last year.

Rounding out the top five is Louis R. Chenevert, who also has $430 million in total wealth. He is CEO of United Technologies and received $27.5 million in 2012.