"Nvidia keeps getting pushed upmarket into an ever-smaller niche, and they don't want to be boxed in," Enderle said.

So if Nvidia must get into CPUs, how should it proceed? Especially in order to avoid the mistakes of the three most recent failed challengers to the Intel/AMD duopoly, Cyrix, PowerPC and Transmeta Corp.?

Analysts offer these four suggestions:

Don't build a CPU from scratch

Nvidia may claim to have the smartest graphics engineers on the planet, and it may claim that But it would have to "commit hundreds of millions of dollars in R&D and lots of time" to build its own CPU from scratch, said Nathan Brookwood, an analyst with Insight64. "[And] while you're busy doing that, the market would have moved on," Brookwood said.