Taiwanese company Silicon Integrated Systems has dismissed rumors that it is going to shut down its PC chipset business . It is now going to concentrate its resources on developing southbridges. SiS will persist with its PC chipset business and satisfy whatever demand there is for its products until 2011. It is currently concentrating on providing notebook chipsets. SiS supplies notebook chipsets to around 20 notebook manufacturers. Cut-throat competition and the precarious state of the global economy have made life difficult for SiS.