Older PC? Expect a decrease in performance after CPU flaw patch, Microsoft warns

Microsoft said onTuesday the patches released to guard against the Meltdown andSpectre security threats slowed down some personal computers andservers, with systems running on older Intel processors seeing a noticeable decrease in performance.

The company expects most users with PCs made during or prior to 2015 running operating systems older than Windows 10 to notice a decrease in system performance.

The security updates also froze some computers running AMDchipsets, Microsoft said in a blog post, citing customercomplaints.

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"We (and others in the industry) had learned of thisvulnerability under nondisclosure agreement several months agoand immediately began developing engineering mitigations andupdating our cloud infrastructure," Microsoft executive TerryMyerson wrote.

Meltdown and Spectre are two memory access flaws thatcould allow hackers to bypass operating systems and othersecurity software to steal passwords or encryption keys on mosttypes of computers, phones and cloud-based servers.

Intel said last week that fixes for security issues in itsmicrochips would not slow down computers, rebuffing concernsthat the flaws would significantly reduce performance.

Rival AMD had also played down the threat, saying itsproducts were at "zero risk" from the Meltdown flaw, but thatone variant of the Spectre bug could be resolved by softwareupdates from vendors such as Microsoft.

AMD and Intel were not immediately available for further comment.