One of the major changes in hard-drive technology in recent years is that most computers now use Serial ATA (SATA) connections, as opposed to the older ATA/IDE connections (also known as PATA, for parallel ATA). All other factors being equal, SATA connections are designed to offer faster data throughput; thinner, more-manageable cables; and better reliability.
While all current Macs except the MacBook Air use SATA connections for internal hard drives—the Mac Pro actually has four internal SATA drive bays—Macs lag behind some Windows PCs when it comes to eSATA, a form of SATA used for connecting hard drives in external enclosures. It’s an alternative to FireWire and USB 2.0, and one that is, in theory, faster than even FireWire 800; it should offer performance comparable to that of an internal SATA drive. If you’ve done any shopping for external hard drives lately, you’ve likely noticed that many inexpensive external hard drives and hard-drive enclosures offer the combination of USB2.0 and eSATA—no FireWire.
(It’s worth noting that there are two main drawbacks to eSATA compared to FireWire and USB 2.0. First, the current implementation of eSATA doesn’t supply power to external hard drives; you need a separate power adapter. Second, while the SATA interface supports hot-swapping, software and hardware limitations in the host computer mean that few computers currently allow hot-swapping of SATA—and, thus, eSATA—drives. This means that eSATA drives must be connected before your computer starts up, and you must shut down your computer before disconnecting such drives. Still, while I’m partial to FireWire for many uses, especially if I’ll be disconnecting and connecting an external drive regularly, eSATA offers great performance at a reasonable price—and yet another option for expanding your storage.)
So how do you add eSATA ports to your Mac? If you’ve got a Mac Pro, you could buy an eSATA PCI Express card; these cards range in price from $40 to nearly $200. But it turns out the Mac Pro has six SATA connectors right on the motherboard (in other words, inside the case). Four of those are used for the computer’s four internal SATA drive bays, but two are just sitting there, unused.
Taking advantage of these two unused SATA connectors, at a relatively inexpensive price, is the purpose of Newer Technology’s $25 eSATA Extender Cable ( ), a nifty accessory that provides two eSATA ports via one of the Mac Pro’s PCI Express slot openings. But the Extender isn’t a PCI Express card; it just replaces one of the PCI Express card retaining covers—the metal pieces that cover the holes on the back of your Mac Pro left by unused PCI Express slots—with a similar plate that offers two eSATA ports. You connect the two included SATA cables to the unused SATA connectors on the Mac Pro’s motherboard and then route the cables to the back of the mounting plate. It’s a bit of a hack, but it’s a clever one.
Once you’ve installed the eSATA Extender Cable, the two eSATA ports it provides work well. Using a quad-interface (eSATA, FireWire 800, FireWire 400, USB 2.0) OWC Mercury Elite hard drive, I copied a 1.2GB folder of files from one of my Mac Pro’s internal hard drives to the external drive using each interface; I also copied that same folder from one internal hard drive to another. The eSATA connection outperformed FireWire and USB 2.0; for example, it took 1:09 to copy the folder via FireWire 400 but only 0:32 to copy it via eSATA. And the eSATA connection was just as fast as copying the folder between two internal drives.
The downside to the Extender Cable itself is the installation process. You see, Apple didn’t mean for the Average Joe to be plugging things into the two unused eSATA connectors on the Mac Pro’s motherboard; the connectors are hidden behind many other components. So installing the Extender Cable involves removing a good number of parts, including several Things You Normally Wouldn’t Touch. For example, on my 2006 Mac Pro, I had to remove the two memory riser cards, the memory bay itself, all four internal hard-drive brackets, the video card, the processor cover, and the front fan assembly. Whew!
Thankfully, Newer Technology provides a pretty good installation manual that includes clear instructions and lots of images. (Note that although the product’s Web page claims the installation guide is “full color,” the guide included with our unit was grayscale. There’s a full-color PDF version of the manual; unfortunately, it’s missing several pages.) Overall, it took me only about 20 minutes to install the Extender Cable. Still, I don’t recommend the procedure to those who aren’t comfortable taking (expensive) things apart and putting them back together again. And keep in mind that if your Mac Pro is still under warranty and you break anything while installing the Extender Cable, there’s a very good chance Apple will refuse to cover the repair.
I suspect that Apple will eventually add eSATA ports to, or make them available as an option for, new versions of the Mac Pro. But for those of us who already have a Mac Pro and would like to have a couple eSATA ports for connecting external drives, the eSATA Extender Cable gives you the option. And it’s tough to argue with the price. As someone who’s comfortable with the insides of a computer, it’s the route I’d take right now. If the installation process was easier, I’d be more comfortable recommending it to everyone.
Updated 6/1/2008: Corrected error about the type of hard drive in current Mac mini models.