Virus Threatens Aptiva PCs

International Business Machines Corp. said several thousand of its Aptiva PCs may be infected with a virus that can shut down the computer. Susceptible machines include models 240, 301, 520 and 580 built between March 5 and March 17. The virus, called CIH, is spread when some files are transferred from one PC to another. IBM said it has contacted most of the affected customers and is providing a program to help eradicate the virus. The potentially affected machines are labeled either AM909, AM910 or AM911 after the “MFG DATE” on the Underwriters Laboratory log on the back of the computers.