Intel is holding an event in San Francisco Thursday that is expected to showcase new tablet-style computers that run the next operating system from longtime partner Microsoft. So a report this week that Intel's CEO had said some less-than-glowing things about Windows 8 was not well timed, to put it mildly.

The big chip maker, after declining to comment on the report Tuesday, on Wednesday issued a statement characterizing it as "unsubstantiated."

Bloomberg,...