Schaub's nightmare, monthlong stretch continued when he threw his first pass of the game for a pick-6, giving the beleaguered Texans quarterback an interception returned for a TD in four straight games.
On the next drive, Randy Bullock hooked a 45-yard field goal try wide left — and the 49ers capitalized afterward again with Gore's touchdown late in the first quarter.
Bullock produced the Texans' lone points with a 41-yard field goal in the third.
"There's a snowball effect. We couldn't get anything going, and when we did, we hurt ourselves," Schaub said. "We stopped ourselves."
Missing three key defenders for the second straight game, San Francisco's opportunistic D didn't flinch and kept the penalties in check after early season problems with flags.
All-Pro linebacker Patrick Willis sat out a second straight game with a groin injury that also kept him out at St. Louis on Sept. 26, and the Niners also missed linebacker Aldon Smith again as he undergoes treatment for substance abuse. Cornerback Nnamdi Asomugha is still nursing a knee injury.
Gore followed up his 153-yard performance in a 35-11 road rout of the Rams with another solid night.
"Once I get going, it's hard to stop me," Gore said.
Schaub wound up 19 of 35 for 173 yards and a sack in the Texans' third straight loss, which came on the heels of a 23-20 overtime loss at home to San Francisco archrival Seattle last week. Houston has its first three-game skid since the end of 2011.
Fans in Texas were already furious and burning his jersey — and there's a sign over one freeway calling for Schaub's ouster. This certainly won't help matters as supporters call for backup T.J. Yates.
In a stadium set to be imploded after the season, Schaub himself imploded. He could be seen muttering to himself with a shell-shocked expression walking off the field as Kubiak buried his face in his hands.
Kubiak turned to Yates in the fourth quarter and Ben Tate lost a fumble on Yates' second play, with San Francisco's Tarell Brown recovering.
The 49ers, who had lost their last two Sunday night games both to the Seahawks, amassed 177 yards rushing with five different players each making a run of 11 or more yards.
San Francisco's 21-point halftime lead matched its biggest under Harbaugh.
Notes: Texans TE Owen Daniels made six receptions for 60 yards, giving him at least one catch in 88 straight regular-season games. ... McDonald sustained a biceps injury in the second half that ended his night. ... The Texans led 159-135 in total yards at halftime. ... Texans DE Antonio Smith saw the end to his streak of four straight regular-season games with at least a half-sack.
AP NFL website: www.pro32.ap.org
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