hp dc7900 sff 85% ps e7400 2gb 160gb dvdrw xpp dg small form factor vista business with xppro installed including downgrade media form factor : small form factor processor : intel core 2 duo processor e7400, 2.80 ghz, 3mb l2 cache, 1066 mhz fsb memory : 2gb (2 x 1 gb) pc2-6400 ddr2 800 sdram memory slots : 4 dimm chipset : intel q45 express storage : 160 gb sata 3.0gb/s 7200 rpm hard disk drive optical drives : sata dvd+/-rw 16x supermulti lightscribe drive bays : 1 x internal 3.5 inch, 1 x external 5.25 inch, 1 x external 3.5 inch os : windows vista business with downgrade to windows xp professional comm : integrated intel 82567lm gigabit network connection graphics : intel graphics media accelerator 4500 integrated graphics audio : integrated hd audio with adi1884a codec, internal pc speaker slot : 1 x low-profile pci, 2 x low-profile pci express x16, 1 x low-profile pci express x1 ports : rear: 6 x usb 2.0, 1 x standard serial port, 2 x ps/2, 1 x rj-45, 1 x vga, 1 x display port, audio in/out; front: 2 x usb 2.0, headphone and microphone power : input voltage 90 264 / 100 240 vac, 50/60 hz, 47 63 hz, active pfc (85% high efficiency) dimensions (h x w x d) : 100 x 337 x 378 mm; weight : 8.5 kg