Millions of clone Pentium motherboards could fail suddenly because they ignore Intel power specifications.
The dodgy boards "skimp on the number of and quality of the capacitors that are required to smooth out voltage spikes around the CPU," according to US trade paper EE Times. This can lead to unexpected power failures that could trash data and files.
In a random test, five out of seven no-name Pentium motherboards failed to meet the Intel spec.
Pentium and Pentium II boards are more likely to suffer power spikes than boards with slower CPUs. And they have tougher voltage and current requirements than earlier Intel chip generations.
But many motherboard suppliers are installing inferior electrolytic capacitors, which dry out in the heat generated by the processor. Within a year or two, PCs built with using these rogue boards, are liable to lock-up.
A motherboard component supplier said the report was "inadequate, incomplete and seriously misleading".
David Fuller, vice president at VXI Electronics, said inadequate PWM integrated circuits, insufficient thermal derating and poor circuit layouts were more serious offenders in the design of onboard solutions.
"To focus on the potential failure of electrolytic capacitors directs attention away from much more serious and frequent sources of failure," he said.
VXI produces voltage regulator modules for Intel motherboards.
Intel said it deplored "anything that could bring the industry into disrepute". It recommended dealers and OEMs to buy their motherboards from approved Intel distribution sources.
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