Channing Frye added 17 points and nine rebounds as the Suns beat the Warriors for the second time in four nights to climb to .500 (25-25) for the first time since Dec. 19.
Ekpe Udoh and Brandan Wright scored 16 apiece for the Warriors. Monta Ellis, the fourth-leading scorer in the NBA at 25.4 points per game, managed just eight on 4 of 13 shooting.
The Suns made it a blowout with a 20-0 run, the last 14 points of the first half and first six of the second, to go up 71-42, Phoenix's biggest lead against anyone this season - up to that point. The Warriors missed 13 shots during that stretch.
Phoenix led by as many as 33 in the fourth quarter.
Jared Dudley scored 13 points and Robin Lopez had 12 for Phoenix. Rookie Zabian Dowdell, signed to fill in for injured Goran Dragic, scored 10 - six more than he'd ever had in an NBA game.
Phoenix, winner of five of its past six overall, won its 28th straight at home against a Pacific Division foe not named the Los Angeles Lakers.
Golden State had won four of five overall, most recently 116-114 over Denver on Wednesday night. Both losses in its past six came against the Suns.
The Warriors - coming off an eight-game home stand - scored the first two points Thursday night, then never led again.
The 14-0 surge to finish the half was part of a 17-3 overall outburst that put Phoenix ahead 65-42 at the break. The Suns shot 60 percent for the half, with Nash leading the way with 14 points and eight assists.
Frye made a jumper, then Vince Carter scored twice to start the third quarter. The 20-point run finally ended when Ellis hit a 14-footer with 8:38 left in the third quarter.
Golden State is 0-3 against Phoenix this season.
Notes: Nash was 3 of 3 at the foul line to move back ahead of Mark Price as the most accurate free-throw shooter in NBA history at just under 90.4 percent. Price is an assistant coach for the Warriors. ... Dragic missed his fifth straight game after cutting his left foot stepping on glass at his home . ... The Suns have won 10 of 14. .. Phoenix goes to Salt Lake City to face Utah on Friday night in the Jazz's first game since coach Jerry Sloan resigned on Thursday. ... The Suns had never led by more than 25 this season and hadn't won by more than 18. ... Ellis was 9 of 30 shooting the past two games against Phoenix.