head to head
Diablo III asks more than Dead Rising, and the gap is variance.

Optimization · Pure Optimization
Mall zombie sandbox where a strict 72-hour schedule turns survival into a routing puzzle.

Optimization · Pure Optimization
A pure loot-and-build treadmill where set-bonus optimisation and Rift pushing define performance.
Dead Rising leans Optimization (Pure Optimization); Diablo III leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Dead Rising
Crowd-clearing melee and psychopath dodging are modestly demanding
Diablo III
Greater Rift pushing has minor mechanical demand in builds
Diablo III leans a little harder on reads, though the gap is small.
Dead Rising
Zombies and psychopaths follow fixed scripts
Diablo III
No meaningful adaptive opponent; co-op is cooperative
Diablo III leans clearly harder on variance.
Dead Rising
Survivor AI pathing and zombie crowds add run noise
Diablo III
Primal Ancient drops and set dungeon RNG drive the grind
Diablo III leans a little harder on optimization, though the gap is small.
Dead Rising
72-hour clock makes routing, scheduling, and PP farming the game
Diablo III
Set bonuses and paragon levelling are almost entirely solvable
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.