Microsoft halts AMD chip patches

Microsoft said on Tuesday it had received reports from customers with PCs that feature AMD chips that their machines stopped loading the Start menu or taskbar after installing Windows operating system security updates.

"To prevent AMD customers from getting into an unbootable state, Microsoft will temporarily pause sending the following Windows operating system updates to devices with impacted AMD processors at this time," Microsoft said in its statement.

Read more: Intel, ARM chip flaws: What you need to know

AMD said on the same day that the issue would affect mainly its decade-old Athlon X2 chips. "AMD is aware of an issue with some older generational processors following installation of a Microsoft security update that was published over the weekend," the US chipmaker said in a statement.

The updates are part of emergency measures aimed at protecting computers and mobile devices from Meltdown and Specter chip design flaws that affect microprocessors made by AMD, Intel and Arm Holdings.

Read more: Last Intel chip fixes due before February

Last week, experts revealed that the two memory corruption flaws could allow hackers to bypass operating systems and other security software to steal passwords or encryption keys, on most types of computers, phones and cloud-based servers.

AMD stock takes hit

The revelation prompted a dash by IT departments to apply software fixes made available by companies like Microsoft. AMD previously said that differences in its chip designs from rival Intel meant its products were at "zero risk" from the Meltdown flaw but that one variant of the Spectre bug could be resolved by software updates from vendors such as Microsoft.

However, Microsoft now said that some AMD chipsets did not conform to technical documentation the chipmaker had provided, preventing Microsoft from successfully patching affected machines. In its blog post, the software giant said the patches had caused computer screens to freeze up, or have so-called "blue screen errors" on Windows 10, Windows 8.1 and Windows 7.

The Washington-based company also said it was working with AMD to resolve the issues and would resume Windows operating system software updates for AMD devices "as soon as possible."

Read more: Intel CEO sold shares before disclosure of chip security flaw

AMD shares fell nearly 4 percent in early trading on Wall Street, after rising nearly 20 percent last week on hopes the software problem may allow AMD to wrest market share from rival Intel.

uhe/jd (Reuters, AFP)