TigerDirect offers the Ultra Limited Edition 450-watt ATX Power Supply (pictured), model no. U12-41526, for $17.97. This $10 mail-in rebate cuts it to $7.97. With $4.89 for shipping, that's $2 under our mention from earlier today, $32 off list and the lowest total price we've seen for a 450-watt power supply. It operates at 72% efficiency and features a 120mm fan, one PCI-Express connector, two Serial ATA connectors, and more. Rebate expires July 31.

TigerDirect also offers the Ultra Limited Edition 550-watt ATX Power Supply, model no. U12-41527, for $20.97. This $10 mail-in rebate cuts it to $10.97. With free shipping, that's $39 off list and the lowest total price we could find. It operates at 72% efficiency and features two 12-volt rails, a 120mm fan, one PCI-Express connector, two Serial ATA connectors, and more.