Product Detail Genuine Dell motherboard for Dimension E521 Case nVidia ChipSet; AMD Athlon 64 Socket; 4 Dual Channel DIMM Support for DDR2 SDRAM 4 GB MAX system memory; 1 16x PCI-Express Video Slot; Integrated nVidia GeForce 6150 LE Graphics Accelerator Integrated 10/100 Lan; 4 Serial ATA Hard Disk Connectors; 1 ATA-66/100/133 IDE Hard Disk Connector One Floppy Connector; 2 PCI Card Slots, 1 1X PCI Express; 4 + 2 USB 2.0 Ports; Integrated audio sound card 7.1 Surround Sound . The "Genuine Dell AMD MotherBoard For Dell Dimension E521Part Number: HK980 CT103 UW457" is best product for you. We recommended Genuine Dell AMD MotherBoard For Dell Dimension E521Part Number: HK980 CT103 UW457