Oh no PC sales are delcining for those that are not gamers... nvidia and amd don't face an issue considering they make chips for tablets and laptops. their PC Desktop market is still going strong, so long as games keep getting visually better, and more dynamic, this will continue, gamers need power to plays those at max settings, gamers are not switching to tablets anytime soon, and laptops are only done if their is a need for portability, on a daily basis. If your laptop is going to sit at home, you should by a desktop. I have a kindle, with android on it, and a windows 7 desktop, enthusiast gaming PC, i can stream my computer to my kindle, and have that processing power at my fingertips.
You people do not understand that different people need PC's for different Reasons, the decline in the market is not in gamers, but people that use computers for word processing or internet. Other gamers, or media professionals MAY switch, if they are okay with paying a lot of money for portability and performance alineware for example. Laptops. Otherwise most are stuck at desktops... its like the average person only need like 3 megabit/s internet connection, most people don't even use 50gb a month on their internet, however others stream constantly and may use a terabyte a month @ 100megabit/s connection. That is another reason why gaming computers, laptops or PCs are expensive, laptops more so, but it is because its not a average persons market, it has grown over the years but it is not the average marketplace. Also desktops will always be more powerful, because their components are bigger, they can fit more transistors in each component.