Computer system with airflow guiding duct

A computer system comprising:

• a chassis comprising a chassis bottom wall, a chassis front wall and a chassis rear wall;
• the chassis front wall defining a first ventilation hole, and the chassis rear wall defining a second ventilation hole;
• a drive bracket being secured to the chassis front wall for receiving disk drives;
• a power supply bracket being secured to the chassis rear wall for receiving a power supply;
• a motherboard secured to the chassis bottom wall between the chassis front wall and the chassis rear wall;
• a memory card secured to the motherboard, a locking component perpendicularly connected to a wall of the drive bracket, a locking hole defined in the locking component, a space defined by the locking component, the drive bracket, and the power supply bracket;
• and
• an airflow guiding duct secured in the chassis substantially covers the space, defining a retaining portion engaged in the locking hole, and extending to cover a portion of the memory card, to guide airflow;
• wherein the airflow is capable of flowing in the chassis via the first ventilation hole, over the memory card, the space and the power supply bracket, and then out of the chassis via the second ventilation hole.