INTEL said this week it has discovered a flaw in its Pentium processors, though it isn't one that computer users are likely to encounter in the normal operation of their machines.

Computers with Pentium processors and Pentium processors with enhanced MMX technology freeze up when a certain set of instructions aimed at crippling the chip are sent to it, Intel said.

Those instructions have to be sent to the chip by the user intentionally, the world's biggest chipmaker said. Turning the computer off and on solves the problem. Rooting out the cause of such flaws is crucial for Intel because its processors have suffered more severe flaws in the past. Intel in May acknowledged an error in some advanced math operations in its Pentium Pro and Pentium II chips. A similar one in its Pentium chips in 1994 cost the company $475 million in replacements. The new flaw doesn't affect Intel's more advanced Pentium II microprocessor or its Pentium Pro, Intel said.