Microsoft said Windows on Arm would initially work on Arm-based chips from Nvidia, Qualcomm and Texas Instruments, which mostly go into smartphones and tablets. Just as Microsoft announced Windows for Arm on Wednesday at CES, Nvidia announced its first CPUs for PCs and servers, code-named Denver, which are based on the Arm architecture.

Nvidia's chief scientist, Bill Dally wrote in an e-mail that the Wintel domination gave users no choice on operating systems or chip architectures, and that Microsoft's announcement will help to free PCs, workstations and servers from the "hegemony and inefficiency" of the x86 architecture.

Intel cannot turn its back on competition, so Nvidia can come and play in the PC market with its Denver CPUs, said Mooly Eden, vice president and general manager of the PC Client Group at Intel.

"At the end of the day, it has to do a lot with the microprocessor. If you look at the performance of an Arm system and you look at the performance of an Intel system, I believe there is a huge difference," Eden said.

Intel's Sandy Bridge chips are able to carry out data-intensive tasks, for example, and questions about Arm's capabilities to handle such workloads have yet to be answered, Eden said.