HP dc5800 Small Form Factor PC - Pentium Dual-Core 2.5GHz XP Pro  - Model KR780UT Intel Pentium Dual-Core E5200 processor (2.50 GHz, 2 MB L2 cache, 800 MHz FSB) 80 GB 7200 rpm SATA 3.0 Gb/s NCQ, Smart IV 1 GB 800 MHz DDR2 SDRAM 6 USB 2.0; 1 serial; 1 external VGA monitor; 1 audio in; 1 audio out; XP Pro Downgrade/Vista