The companies that are working in the IT market have to use the same strategies that other companies are using in other markets: automotive market, food market, etc.
In every market there is a leader, there are few chasers, and there are a lot of underdogs. In the CPU/GPU market the leader is without a doubt Intel, a chaser is NVIDIA and an underdog is AMD. There are a lot of other companies, like Imagination Technologies, ARM, VIA, Applied Micro, and so on, but today I want to talk about the strategies of these three companies.
It will be an odd article for a lot of you, but I hope that it will be useful to you to understand the inner working of IT market. To do this, I will use a book that I consider a milestone: Marketing Warfare, by Al Ries and Jack Trout. I suggest you to buy it. ;)