This is a Dell replacement power supply for Dimension models E310,E520,E521,3100,5100, L305N-00, HP-P3077F3 and HP-P3077F3P .

Dimensions: 6" X 5.5" X 3 7/8" (L x W x H)
Connectors
1 ATX connector (24 pin)
1 12V connector (4 pin)
1 IDE 4 PIN connector
1 Floppy 4 PIN connector
4 SATA Connectors