Synology Power Supply Unit PSU 250W_4, Power supply - internal, 250 Watt, 1 x power 24 pin ¦ 1 x 12 pin internal power ¦ 1 x 8 pin PCI Express power, Disk Station DS1817+. Buy Synology PSU 250W_4 power supply unit 250 W 24-pin ATX Metallic online with confidence, security and peace of mind. All transactions are covered under the PayPal Buyer and Seller Protection programme.