Dell Precision T7400 (Late 2007) - Manual (Page 182)

182 Adding and Replacing Parts
4 Disconnect the power cable from memory riser card 1 and 2.
5 Grasp the memory riser card 1 at each corner and lift memory riser card 1
and attached card 2 from the DIMM_1 and DIMM_2 slots on the system
board.
If a card is difficult to remove, gently ease it back and forth to remove it
from the connector.
1 power connectors (4) 2 memory connectors (4)
3 securing clips (2)
3
2
1