ASRock P4S55FX User Manual - Page 12

2.3 Installation of Memory Modules (DIMM) P4S55FX+ / P4S55FX motherboard provides four 184-pin DDR (Double Data Rate) DIMM slots, and supports Dual Channel Memory Technology. For dual channel configuration, you always need to install identical (the same brand, speed, size and chip-type) DDR DIMM pair in the slots of the same color. In other words, you have to install identical DDR DIMM pair in Dual Channel A (DDR1 and DDR3; Blue slots; see p.7 No. 6 / p.8 No.6) or identical DDR DIMM pair in Dual Channel B (DDR2 and DDR4; Black slots; see p.7 No. 10 / p.8 No.10), so that Dual Channel Memory Technology can be activated. This motherboard also allows you to install four DDR DIMMs for dual channel configuration. In that case, it is not necessary to install identical DDR DIMMs in all four slots; however, it always requires identical DDR DIMM pair to be installed in the slots of the same color. Please refer to the Dual Channel Memory Configuration Table below. Dual Channel Memory Configurations DDR1 DDR2 DDR3 DDR4 (Blue Slot) (Black Slot) (Blue Slot) (Black Slot) (1) Populated - Populated - (2) - Populated - Populated (3)* Populated Populated Populated Populated * For the configuration (3), you may: install identical DDR DIMMs in all four slots or install identical DDR DIMM pair in DDR1 (Blue Slot) and DDR3 (Blue Slot) and identical DDR DIMM pair in DDR2 (Black Slot) and DDR4 (Black Slot) 1. If you want to install two memory modules, for optimal compatibility and reliability, it is recommended to install them in the slots of the same color. In other words, install them either in the set of blue slots (DDR1 and DDR3), or in the set of black slots (DDR2 and DDR4). 2. If only one memory module or three memory modules are installed in the DDR DIMM slots on this motherboard, it is unable to activate the Dual Channel Memory Technology. 3. If a pair of memory modules is NOT installed in the same Dual Channel, for example, installing a pair of memory modules in DDR1 and DDR2, it is unable to activate the Dual Channel Memory Technology . 12