Microsoft launched the Surface Pro 4 and the Surface Book on Tuesday, showing its commitment for the hardware industry and reiterating that it has no other plans than to continue expanding not only in the tablet business, but also in laptops with new devices.

While that's indeed a good thing for Microsoft's customers who expect the company to bring out as many devices as possible, these announcements are worrying for PC makers who were or are still working together with the Redmond-based software giant on a number of projects.

Companies such as Dell, HP, Toshiba, and others, which are all building laptops, tablets, and 2-in-1s with Microsoft's Windows operating system, are now competing directly against the software giant because of the new devices it brought to the market.

And according to various reports, many are concerned that Microsoft's evolution in the hardware business could hurt their sales because more buyers would be tempted to purchase a Surface device instead of their own.

Microsoft, the hardware company

And all these concerns certainly make sense. Back in 2012 when Microsoft launched the Surface RT, a tablet that could double as a laptop, several PC manufacturers, including Acer, accused the company of cannibalizing sales of the PC industry by launching devices that are supposed to compete with their own.

Acer's CEO himself said at the time that Microsoft should continue investing and improving in the software business, while letting others build hardware to run these products.

Microsoft has instead continued investments in hardware and the Surface lineup is now at the fourth generation, while also bringing us the very first laptop ever created by the software firm.

Whether this can affect sales of the other PC makers only time will tell, but competition seems to be fairly productive on the short term. HP has already announced some very exciting Windows 10 devices and others are expected to do the same in the coming weeks, just ahead of the holiday season.