The three personal computer giants debuted personal computers on Monday that are designed to work with Alexa, part of a push by Amazon to spread its voice assistant to more third-party devices. The companies announced the new computers against the backdrop of this week’s annual International Consumer Electronics Show, in Las Vegas.

Although most people interact with the Alexa voice assistant through Amazon’s web-connected speakers, the Echo and the Echo Dot, the online retail giant has been increasingly courting third-party companies to embed Alexa in their own devices.

Amazon (AMZN), Google (GOOG), and Microsoft (MSFT) believe that voice-activated assistants are a new frontier for interacting with computers. As a result, these companies are investing heavily in voice technology and are increasingly debuting products like Google and its Google Home speakers that use voice assistants to do things like play certain songs when asked.

People can already access Alexa on their PCs through an Amazon-sanctioned website for developers to test their Alexa apps, or skills, built for the Echo. The new HP Inc. (HPQ), Asus, and Acer computers, however, come with features specifically designed for Alexa and make it easier to access the service rather than having to visit a website.

For example, the HP Pavilion Wave comes with a special LED that lights up to show that Alexa is listening. That computer, like Acer’s Amazon-supported PCs, also contains custom Intel audio processors that are intended to help Alexa better hear and respond to people’s voices.

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People can use Alexa on their computers, for example, to check their online calendars, play music or podcasts, and control Internet-connected devices like lights and thermostats in their homes, Acer said.

“Hands-free access to Alexa on PCs can be helpful to customers in many ways, like making it simple to interact with your smart home, get news or weather, set timers, and more,” Amazon Alexa vice president Steve Rabuchin said in a statement. “This is a big step toward making Alexa available wherever customers might need her.”

Alexa’s integration into PCs poses a challenge to Microsoft, which is trying to push its Cortana voice-activated assistant as the preferred way for people to talk to their Windows-powered computers for performing simple tasks. The more people use Alexa instead of Cortana when scheduling appointments to their online calendars, for instance, the less data Microsoft collects for improving Cortana.

Vuzix, a technology and consumer gadget company, also said over the weekend that its Vuzix Blade augmented reality glasses would come embedded with Alexa. The $1,000 glasses can superimpose digital images on the real world, and with Alexa, people can presumably ask the eyewear to also show them weather information, sports statistics, or restaurant menus, according to USA Today.