Microsoft's upcoming Windows 8 operating system is going to be a threat to open platforms, Valve co-founder & managing director Gabe Newell believes.

Newell and his video game development company Valve produced some of the most acclaimed titles like Half-life and Left 4 Dead. They are also responsible for a popular online distribution service for video games called Steam.

In a recent interview with Casual Connect at a videogame conference in Seattle, Newell said Windows 8 OS would hurt open computing platforms, which have helped makers of computer games in flourishing without any support from Microsoft.

Expressing his disapproval for Windows 8 OS, Newell said, "I think Windows 8 is a catastrophe for everyone in the PC space. I think we'll lose some of the top-tier PC/OEMs, who will exit the market."

He added that the new OS would destroy margins for a bunch of people, and they alternatives should be found to hedge against that possibility.

Separately, Rob Pardo, executive vice president of game design at blizzard, went on popular social-networking site Twitter to confirm that Windows 8 OS is not going to present much of a great experience for his company.