A Look at Seagate’s FreeAgent GoFlex 4TB External Disk Drive & Western Digital’s USB 3.0 PCIe Card in a MicroServer

By: John Stutsman

I’m always looking at hard drives and ways that I can expand my storage capacity to better organize my systems and backups of those systems. The following is not strictly a review of the FreeAgent GoFlex 4TB or the WD USB 3.0 PCIe Card but more of a chronology of how well they work in my systems and a few basic performance ratings.

Not long ago I noticed that Amazon had a price of $229 on Seagate’s FreeAgent GoFlex 4TB External Desk Drive STAC4000100. More recently, I’ve seen prices for the GoFlex 4TB hover just above $200. Always before I considered myself a Western Digital fan boy but after testing the Seagate ST3000DM01 in my MicroServer I’ve been substantially more open minded about exploring off the Western Digital reservation.

What I found very intriguing about the 4TB GoFlex was that at its core was the 4TB Seagate Barracuda XT ST4000X000 SATA 6Gb/s Hard Drive that was, and still is, selling at a substantially higher price than the 4TB GoFlex when it is sold as a bare drive outside the external case. There is a video out that gives step by step instructions on how to remove the enclosure/casing from around the ST4000X000 so that it can be used inside a desktop – which obviously violated the warranty on the GoFlex. Removing the ST4000X000 from the GoFlex housing is beyond the scope of this paper.

I ordered the GoFlex 4TB intending to try it out on several of my machines. I also ordered Western Digital’s USB 3.0 PCIe Card which would fit perfectly inside my MicroServer.


The Seagate GoFlex 4TB USB 3.0

The GoFlex 4TB Unpacked


After the GoFlex 4TB arrived I unpacked it and set it up. I first attached it to the USB 3.0 port on the back of my X58.


The GoFlex 4TB USB 3.0 attached to the GA-X58A-UD3R USB 3.0 ports on back and powered up


I powered up the GoFlex 4TB. My X58 saw it right away. I opened up Windows Explorer and check out the directory.

While I didn’t try it in this exercise — the GoFlex 4TB comes supplied with software to set up automatic backups to the GoFlex 4TB. I’m sure their software is good – it just wasn’t the reason I bought the GoFlex 4TB to try out and I already have a backup solution that I am using.


Directory of what is on the GoFlex 4TB as seen in Windows Explorer



A detailed directory view of what came on the GoFlex 4TB in Windows Explorer

Checking out the Properties of the GoFlex 4TB it showed the available capacity on the 4TB drive as 4TB (less some space being used by the included Seagate software mentioned above).


Properties of the GoFlex 4TB


As shown below the performance of the GoFlex 4TB (and the underlying ST4000X000) on the USB 3.0 with reads and writes around 170 MB/sec.


ATTO performance of GoFlex 4TB on X58 USB 3.0 rear Port


I next moved the GoFlex 4TB to one of the USB 3.0 ports on the back of my Z68 and got similar results that I had achieved with the X58’s 3.0 ports, i.e. reads and writes between 160 & 180 MB/sec.

While the GoFlex 4TB was attached to the Z68’s USB 3.0 port I copied about 400GB of files to the GoFlex 4TB over about a 70 minute time period.


Atto performance of GoFlex 4TB on Z68 USB 3.0 rear Port



Western Digital’s USB 3.0 PCIe Card in a MicroServer

I mentioned earlier that I also picked up a WD USB 3.0 PCIe Card to try out in my MicroServer. The WD USB 3.0 PCIe Card arrived in a plain box. The Card comes with a drivers disk that you install before you install the PCIe Card. I installed the drivers onto the host operating system on my MicroServer which is Windows Server 2008-R2.


The WD USB 3.0 PCIe Card and Driver Install Disk

Installing WD Driver onto the MicroServer using an external USB drive

The MicroServer powered down and placed on grounding mat -- preparing to remove the motherboard/system-board

After installing the Western Digital drivers for the WD USB 3.0 PCIe Card I powered down the MicroServer, unplugged it, and moved it to my workbench and set it onto a grounding mat. I then attached a ground strap to myself and began taking the MicroServer apart. You’ll observer in the first picture below (left) that the dual Intel NIC that I had installed earlier has been replaced by a single NIC Intel card. In the second picture below (right) we see the WD USB 3.0 PCIe Card installed in the Mother Board, or System Board, of the MicroServer.

Below (left) we see the MicroServer Mother Board from the back with both PCIe Cards installed and the card NIC and USB connection ports clearly visible. Below (right) is a top view of the MicroServer Mother Board with the cards installed.

Installing a second PCIe card into the MicroServer was problematic in one respect because by filling up both slots I lost my empty slot to run my cable (see lower left picture) from my eSATA port on the back of the MicroServer into the case to plug into the WD Green drive in the ODD in the top of the MicroServer.

The solution I found was to bend the bracket, also known as the PCI holder, that anchors the top of the PCI brackets 1 & 2 to the case. Just a “slight” bend was all that was necessary and is clearly visible in the lower (right) picture. Another option I considered was to use a dermal to make a new hole in the case for the cable – bending the bracket, PCI holder, was easier and probably the better solution in my estimate.

Below, the Western Digital software successfully installed onto the MicroServer before opening up the MicroServer and installing the WD USB 3.0 PCIe Card.

WD drivers installed for USB 3.0 PCIe Card

Below, is the performance of the GoFlex 4TB using the WD USB 3.0 PCIe Card in the MicroServer. The read and write speeds are just over 140 MB/sec which is roughly 30 MB/sec worse than the performance achieved with the USB 3.0 ports that are available on the X58 and Z68 boards tested earlier.


ATTO performance of GoFlex 4TB USB 3.0 with WD USB 3.0 PCIe Card mounted in MicroServer


The performance in the MicroServer is respectable for the GoFlex 4TB with the WD USB 3.0 PCIe Card though it doesn’t measure up to the performance I saw with the Seagate 3TB ST3000DM001 when it was directly installed to a SATA II port inside the MicroServer.

Compared to a directly installed ST3000DM001 the GoFlex 4TB has the additional overhead of the WD USB 3.0 interface card as well as the interface of the Seagate external enclosure USB 3.0 to SATA base. Compared to the GoFlex 4TB’s performance in the X58 and the Z68 the WD USB 3.0 card in the MicroServer is apparently not as fast as the direct motherboard USB 3.0 connections on the X58 and Z68.


USB 2.0 Performance Comparisons

For comparison, I check the performance of the GoFlex 4TB when plugged into one of the USB 2.0 ports in the MicroServer. The ATTO performance charts below show that the GoFlex 4TB’s performance when attached to the WD USB 3.0 PCIe Card (below left) was about five times the performance when it was attached to a USB 2.0 port (below right) on the MicroServer.

Next I compared the relative performance of the WD USB 3.0 PCIe Card to the USB 2.0 ports in the MicroServer by attaching a WD 2TB Elements USB 2.0 External disk. Surprisingly to me, the WD 2TB Elements USB 2.0 External Disk performed slightly better when attached to the WD USB 3.0 PCIe Card (below right) versus the USB 2.0 port (below left) on the MicroServer.



In the short time that I’ve used it the GoFlex 4TB has been reliable and relatively fast low cost mass storage. The WD USB 3.0 PCIe Card provides a low cost option of attaching 2 external devices to my MicroServer – in the case of the GoFlex 4TB – I could add 2 GoFlex 4TB’s for a total of 8TB of additional storage on my MicroServer. I could do likewise with my Z68 and X58 machines.

Bottom line: I like the GoFlex 4TB. I’m impressed with its ease of use and its speed for an external drive and of course I’m impressed by its massive capacity. I also like the WD USB 3.0 PCIe Card – it expands my options with my MicroServer (the MicroServer is not built with any USB 3.0 ports) and it is an option for adding additional USB 3.0 ports to my other machines. It was interesting to observer that a regular USB 2.0 external drive performed about 16% better when attached to the WD USB 3.0 PCIe Card versus a USB 2.0 port in the MicroServer.

The big question remains: how would the Seagate ST4000X000 that makes up the core of the GoFlex 4TB perform on it’s own as a bare drive directly connected to a SATA III or SATA II port?

Answering that question will have to wait till the next installment (Part 2) of this report.

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5 Responses

  1. Factoring says:

    Wow, now I am looking for external hardrives, I've never used them before..

  2. Rob says:

    Great job…something new to play wit now.