Wallace threw both of his touchdown passes on long completions to Ja-Mes Logan, who finished with six receptions for 122 yards. Ole Miss (5-3) won its second straight game, finishing with 569 total yards.
Ole Miss led 17-0 after one quarter, 24-7 at halftime and erased any remaining doubt with 21 points in the third quarter.
It was an easy victory for the Rebels, who needed one after a brutal month of games that included losses to Alabama, Auburn and Texas A&M, as well as last week's upset victory over LSU.
The Rebels took a 14-0 lead in less than seven minutes. The first touchdown was a perfectly placed 37-yard throw from Wallace to Logan while the second was a 40-yard run by Walton.
Idaho came into the game as a 41-point underdog and had already been blown out by programs like North Texas and Wyoming. Even worse, the Vandals started Davis, their third string quarterback, on Saturday because of injuries to Chad Chalich and Joshua McCain.
But they stayed competitive in the first half and put together a 75-yard drive -- capped by a 2-yard TD run by Davis -- to pull within 17-7 early in the second quarter.
Ole Miss led 24-7 at halftime and quickly added to the advantage with a 65-yard heave from Wallace to Logan to make it 31-7 with 9:26 left in the third quarter.
The Rebels now have a week to rest before a Nov. 9 game against Arkansas in Oxford. A win would give Ole Miss bowl eligibility for the second straight season.
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Linebacker Myles Jack, who suffered a season-ending knee injury, said Thursday he decided to leave UCLA and enter the 2016 NFL draft because he wants to be compensated for his skills.
The tougher tests await down the road for No. 3 Baylor Bears, but coach Art Briles has seen enough of his Bears to know this is his best team.
A decision has been made that Randy Edsall will not be the football coach at Maryland next season, and discussions are taking place about how and when to separate, a source said Thursday night.
Florida State running back Mario Pender has been released from the hospital but could be given a medical redshirt if he cannot return to the field this season.
Tennessee chancellor Jimmy G. Cheek has issued a statement amid rumors that alleges coach Butch Jones fought and punched senior offensive lineman Mack Crowder during a fall practice session.
With the addition of a few tweaks, UConn football coach Bob Diaco is still planning to bring a rivalry trophy with him to Florida on Saturday when the Huskies play UCF.