HP ML530 ProLiant ML530 Generation 2 Server Setup and Installation Guide - Page 242

System LEDs and Switches Expansion Slot Speed LEDs The bus architecture delivers matched speed of expansion boards on the same bus. IMPORTANT: Always pair expansion boards of the same speed on the same bus for optimal performance. If expansion boards of different speeds are installed on the same bus, the server operates both boards at the lower frequency, resulting in potential bottlenecks. Use Figure C-5 and Table C-6 to identify the speed for each PCI slot and to help ensure optimal performance. Figure C-5: Expansion slot speed LEDs Table C-6: Expansion Slot Speed LEDs LED 1 2 3 4 Slot Speed 33 MHz PCI 66 MHz PCI 66 MHz PCI-X 100 MHz PCI-X C-8 HP ProLiant ML530 Generation 2 Server Setup and Installation Guide