StarTech.com PEX56KIM, 56 Kbit/s, PCI Express, Conexant - CX95610, V.44, Windows 8 (32/64bit), 7 (32/64), Vista(32/64), XP(32/64), Windows Server 2008 R2, 2003(32/64), 0 - 40 °C StarTech.com PEX56KIM. Modem speed: 56 Kbit/s, Interface: PCI Express, Chipset: Conexant - CX95610. Data compression: V.44. Compatible operating systems: Windows 8 (32/64bit), 7 (32/64), Vista(32/64), XP(32/64), Windows Server 2008 R2, 2003(32/64). Weight: 1.31 oz (37 g), Depth: 2.36" (60 mm), Height: 2.64" (67 mm). Cables included: Phone (RJ-11)