NEW YORK ( TheStreet) --We Apple ( AAPL) investors typically view Steve Jobs' health as the biggest risk to the stock, but there's a potentially greater threat: Google's ( GOOG) new operating system. No, I'm not talking about Android. I'm talking about Chrome OS. People are focusing too much on Android, which has already overtaken Apple's iOS in terms of the global unit shipment rate, at least according to some estimates. While Android is a capable and interesting operating system, especially given that it's free and ties into Google's plethora of free services, ranging from maps to docs, it fundamentally doesn't change the game much, if at all. Its main architectural paradigm has more in common with Apple's iOS than any fundamental difference. Chrome OS, on the other hand, is as fundamental a re-think of the operating system, the computer architecture and the nature of applications as we have seen since at least the advent of the PC in the late 1970s. Its pure cloud architecture means lesser hardware requirements, more security and faster boot-time. Google's Chrome OS can threaten Apple in at least three ways: 1. Starting some time around July or August, Google's partners Samsung and Acer will launch laptops and perhaps also a desktop or two, based on Chrome OS. I am guessing laptops will start at $299 and "naked" desktops at $149. Given the superb performance of these Chrome OS PCs, with boot-up times (from cold) of less than even Apple's MacBook Air, some consumers and enterprises will pick Chrome OS PCs over the much more expensive Apple PCs. To wit, the cheapest Mac laptop starts at $999. A service plan starts at $249. So effectively, you're out at least $1,248. Chrome OS laptops at $299 without the need for a service plan will look extremely attractive in comparison. I also predict that Chrome OS laptops will become available for sale in entirely new places: hotels, airplanes and even vending machines. Why? Unlike a regular Apple or Microsoft ( MSFT) PC, there is almost zero set-up time, making an impulse purchase/replacement realistic.