More than half a million Sony laptops sold this year contain a software bug that could lead them to overheat, the company said Wednesday.

In a statement on the Sony support site for Vaio laptops, Sony posted a notice from Mike Lucas, senior vice president of Vaio for Sony, stating "Recently, we became aware of a potential issue affecting certain units within the VPCF11 and VPCCW2 series of notebook PCs."

  Sony has recorded 39 cases of overheating among Vaio F and C series laptops that have been on sale since January.

A bug in the heat management system of the BIOS software is to blame. Sony is asking users to either update the software themselves or return their laptops so it can apply the update.

  The fault affects 535,000 computers although Sony is asking a total of 646,000 owners to update their machines. The additional 111,000 machines are susceptible to several less serious problems that have also been found in the software, said Sony.

  BIOS is present in every PC and runs below the operating system, controlling the most basic functions of the computer and interaction between major components. It′s usually invisible to users except for a BIOS start-up message that is typically seen when a PC boots.

Laptop models with the problem are the VPCF119FJ/BI, VPCF118FJ/W, VPCF117FJ/W, VPCCW29FJ/W, VPCCW28FJ/P, VPCCW28FJ/R, VPCCW28FJ/W, VPCF11AFJ, VPCF11AGJ, VPCF11AHJ, VPCF11ZHJ, VPCCW2AFJ, VPCCW2AHJ, VPCCW25FG/B, VPCCW25FG/P and VPCCW25FG/W.

  Visit Sony Support Site