If these power supplies are not connected, the device may not work at all or the system may become unstable. Also, when adding several high-demand components, users should exercisattaranise caution to avoid overloading their power supply unit (PSU). The stability & performance of your system depend on your PSU having the right connectors and a sufficient wattage. Enhancing PCIe Slot Performance with System Upgrades As technology develops, PCIe slot performance and overall computing power can be greatly increased by upgrading your system.