NVIDIA this morning turned its attention to its mainstream notebook graphics chips by filling out its GeForce 200M range. The GTS 250M and GTS 260M are targeted at desktop replacement class but relatively affordable notebooks with 28W of peak power. They each have 96 visual processor cores and 1GB of GDDR5 memory on a 128-bit bus. The two only differentiate in clock speed, as the 250M has a 500