Twenty-one computer hardware and software companies have joined forces to support an advanced microprocessor for computer workstations.

The group is viewed by some industry observers as an effort to counter the powerful influence of several leaders in the workstation field, including Sun Microsystems Inc. and Hewlett-Packard Co.It also appears to be an attempt to limit the influence of Intel Corp., the maker of the microprocessors that act as the brains of the majority of personal computers sold worldwide, observers say.

Among the members of the new group, announced recently, are Digital Equipment Corp., the world's second-largest computer maker, and Compaq Computer Corp., the largest maker of IBM-compatible personal computers. The group also includes Microsoft Corp., the world's largest maker of personal computer software.

Workstations are desktop computers that are more powerful and expensive than PCs. Originally designed for scientific and engineering uses, they increasingly are finding more mainstream applications.

The companies in the consortium, called the Advanced Computing Environment, said they will standardize their workstation hardware and software around microprocessors made by Mips Computer Systems Inc. of Sunnyvale, Calif.

The Mips chips use a technology called reduced instruction set computing, which speeds processing by simplifying the commands a computer must execute. RISC-based processors are the chips of choice for workstations, but there are a number of incompatible RISC chips on the market.

Though Mips is small, its micro-processors already have been adopted by Digital for many of its work-stations. The consortium is expected to elevate its processors to the level of a de facto industry standard.

An executive of one of the participating companies, who spoke on condition of anonymity, said the group's aim was to allow computer hardware and software companies to focus their research and development efforts.