Western Digital Caviar Green 3TB 64MB Cache Internal Hard Drive for $89.99 shipped. You can use coupon code FREESATA3CM to get a free SATA III red flat cable too. Here is a screenshot for your reference. This is part of WD’s GreenPower lineup, which reduces energy usage. It features 64MB cache and uses SATA 6.0Gb/s interface. Note that it comes in OEM packaging, which means no pretty retail box but is otherwise identical.