Apple’s new processors are fast – and we’ve seen that they are faster than Intel’s laptop processors – but above all they are energy efficient. It is the ARM64 architecture that forms the basis of the CPU cores and makes them so efficient, so the question is how they stand compared to other computers with the same architecture.

Our colleagues at PCWorld have run a series of tests on a MacBook Air with M1 processor and Microsoft’s Surface Pro X. The latter has a processor called SQ1 which has been developed in a collaboration between Qualcomm and Microsoft, and has the ARM version of Windows 10 running on it.

The test could be performed because, after some delay, Microsoft has finally released the 64-bit x86 code emulator for Windows on ARM. As a result modern programs compiled for Intel and AMD’s 64-bit processors can ow run on the platform.

In Geekbench 5, the M1 MacBook Air got 1,750 (single-core) and 7,454 (multi-core) points, while the Surface Pro X gets 731 and 2,734 points. Cinebench R23 gave 1,496/6,838 and 371/1,604 points respectively.

A Handbrake conversion of a 12-minute 4K video to 1080p with h.265 took 326 seconds with optimizations for the M1 processor, 1,415 seconds on the M1 Mac without optimisation. It took 9,571 seconds on the Surface Pro X.

Microsoft promises further optimisations of x86 code on Windows on ARM, and if versions compiled directly for ARM64 are released, they will go faster, but PCWorld notes that miracles are required for Windows on ARM to become something.

Also read: Apple M1 runs Windows on ARM faster than Surface Pro X

Wondering whether to buy an M1 Mac? Read our guide to the pros and cons: Should I buy an M1 Mac?

This article originally appeared on Macworld Sweden. Translation by Karen Haslam.