Even though SiS has thier own fabs, they're contracting
out production of their 650 and 651 chipsets to UMC.
Silicon Integrated Systems (SiS) is said to have started moving production
of its current major products, the SiS650 and SiS651 integrated chipsets, to
new foundry partner United Microelectronics Corporation (UMC) to resolve their
recent tight supply.