Motherboard assembly and central processing unit expansion card

A motherboard assembly comprising:

• a motherboard comprising:
• a first board;
• a central processing unit (CPU) socket mounted on the first board;
• a plurality of first memory slots mounted on the first board and electrically connected to the first CPU socket;
• and
• a first connector mounted on the first board and electrically connected to the first CPU socket;
• and
• a CPU expansion card comprising:
• a second board;
• a second CPU socket mounted on the second board;
• a plurality of second memory slots mounted on the second board and electrically connected to the second CPU socket;
• a second connector electrically connected to the second CPU socket and mounted on a bottom side of the second board to be inserted into the first connector of the motherboard;
• a base board;
• and
• two sidewalls extending in a substantially perpendicular manner from opposite sides of the base board, wherein a receiving space is bounded by the base board and the sidewalls to receive the second board of the CPU expansion card, two fixing sheets extend in a substantially perpendicular manner from a bottom side of the base board, a first through hole is defined in each fixing sheet, two second through holes, corresponding to the first through holes, are defined in the first board, the CPU expansion card is fixed on the first board through two fasteners extending through the first through holes to engage in the second through holes.

An assembly comprising:

• an enclosure comprising a sidewall;
• and
• a motherboard assembly comprising:
• a motherboard mounted on the sidewall, the motherboard comprising:
• a first board;
• a central processing unit (CPU) socket mounted on the first board;
• a plurality of first memory slots mounted on the first board and electrically connected to the first CPU socket;
• and
• a first connector mounted on the first board and electrically connected to the first CPU socket;
• and
• a CPU expansion card comprising:
• a second board;
• a second CPU socket mounted on the second board;
• a plurality of second memory slots mounted on the second board and electrically connected to the second CPU socket;
• a second connector electrically connected to the second CPU socket and mounted on a bottom side of the second board to be inserted into the first connector of the motherboard;
• a base board;
• and
• two sidewalls extending in a substantially perpendicular manner from opposite sides of the base board, a receiving space is bounded by the base board and the sidewalls to receive the second board of the CPU expansion card, two fixing sheets extend in a substantially perpendicular manner from a bottom side of the base board, a first through hole is defined in each fixing sheet, two second through holes, corresponding to the first through holes, are defined in the first board, the CPU expansion card is fixed on the first board through two fasteners extending through the first through holes to engage in the second through holes.