"You will get a better return on investment from network bandwidth" than new computers, he said.
Gartner said users should use existing hardware longer to maximise return on investment, and use asset management software to control the extension of PC deployment life.
Competition will intensify in the PC hardware market, where standardisation is producing commodity products and ever-lower prices, Gammage said
He also warned that tough times for hardware manufacturers could prevent important innovations reaching business users.
"The move towards more standardised computing platforms will lead the industry to invest less money in research and development," said Gammage.
"While the industry has a number of exciting developments in the pipeline, there is now a question mark over the industry's ability to bring these developments to market in a way that will add real business value to users."
Gammage predicted the big three PC and server vendors - IBM, HP and Dell - would survive, while smaller players could find themselves squeezed out of the market or forced into mergers or alliances.