One problem any company has in buying AMD is Intel. Intel basically lets AMD survive eating the scraps and offal of the market, while Intel commands the market. AMD buyers represent the catfish in the botton, sucking off the bottom, and suffering with inferior hardware because it's all they can afford. Intel lets this happen.
If someone like Samsung takes over AMD, Intel might feel threatened. They might decide they can lower their profits a little bit, and kill the catfish before it gets too big to try to eat from the top. Intel's processors are cheap to make, perform very well, and have great brand recognition. They also own their fabs. Competing against them with AMD designs is only hopeful with the Brazos design. With Bulldozer or Piledriver, because the cost of the chip for the performance is much lower, Intel can easily make this line irrelevant by adjusting pricing.
ATI would still be competitive, but the more processors sold with GPUs, the less of the market for discrete cards, especially as they get more powerful.
I think most companies realize Intel would react strongly to any threat, and that's got to make them a little worried. Or more than a little.