Windows Prism Binary Translation Doubles Instruction Counts on Arm
On Binary Translation and Its Consequences
Microsoft's Prism translator lets x86-64 Windows apps run on Arm, but Geekbench 7 reveals a steep cost: roughly twice as many aarch64 instructions execute under translation, with vector-heavy workloads like Video Player hit hardest. Testing on Snapdragon X2 Elite, Neoverse N1, and N2 shows Qualcomm's cores absorb the overhead better thanks to wider out-of-order engines and larger caches, though every core still loses several generations of performance.
A Geekbench 7 workload will execute roughly twice as many aarch64 instructions as x86-64 ones when going through binary translation, as a rule of thumb.