by Greg Ross
Do you have too many USB devices? Enough that you are starting to have bandwidth issues? Or are you craving a faster external hard drive for backups or media sharing or as a network drive? Do you desperately need more hard drive space for your laptop, but do not want to get another laptop drive? If you answered yes to any of these questions, do yourself a favor and look into a PCMCIA or ExpressCard eSATA Card to increase your performance. I did, and here is my take on the Vantec eSATA PCMCIA Card!
Reasons for Buying
The big red box certainly looks attractive…
Ever since purchasing my notebook, I have had issues with USB devices. They work perfectly fine, but the bandwidth is just not enough. Most of my devices do not need too much bandwidth, so I have been able to just ignore the problem, except for my three external hard drives. They are slow – really slow – when running on a USB port, and it was to the point that backing up my files or using a drive as a deep media storage bin was truly a poor experience. I needed some way to speed up my drives, and I had an empty PCMCIA card slot. I was able to get this card from NewEgg for $31.58 after shipping.
Just to give you an idea, here is a sample HDD analyses with HDTune with my hard drive and all my other devices plugged in over USB. Please note, most people will never deal with this problem and I am showing this to illustrate my point.
Yes, it really is that bad.
- Model: UGT-ST350CB
- SATA Ports: 2
- Supported OSes: Windows 98SE/NT4.0/ME/2000/XP (also claims to be Vista compatible according to NewEgg customer comments)
- Max Speed: SATA-II @ 1.5Gbps (Giga-bits per second)
- Supported Hard Drives: SATA II @ 1.5Gbps and 3.0Gbps (but it limits 3.0 drives to 1.5 speeds)
Installation of the eSATA PCMCIA controller went smoothly and without error. Push in the card, and then when Windows asks you to point towards the drive in the Hardware Installation Wizard, you point towards the CD drive. (A Vantec CD comes in the package.) Easy!
After my card was installed, it registered as a Silicon Image SCSI Controller but it does work with SATA!
Notice it is listed as a SCSI controller…(view large image)
The only minor problem with installation was when I attached an external drive into the card when the laptop is running. It worked perfectly fine, and the drives are indeed hot-swappable as Vantec claims. But there was about 3-5 seconds in which the laptop just froze. As in comes to a complete halt, cannot move the mouse, frozen. I am assuming that this is a driver issue that could be corrected in the future, but as long as you do not shut the laptop down and give it a little time it will resume and run just as fast and bug-free as before. If you turn the laptop on with the drives plugged in, I noticed a small freeze before trying to sign in and type my password.
Plug it in, plug it in…(view large image)
Please, keep in mind that this freeze only occurs when the drive is plugged in or turned on. During normal usage there is no lag or problems.
Baseline USB Performance for a 2.5 and 3.5 External Hard Drive
Now that you have seen my pain, let me show you a bandwidth analysis that most people will end up seeing. Keep in mind that I was only able to get these speeds when the one hard drive I was testing was the ONLY device I had plugged in but most people will see these speeds no matter what.
As a reference, the two drives that will be tested today with the PCMCIA card are:
- Hitachi HTS721010G9AS00 2.5 Hard Drive contained within a Vantec USB & eSATA External Case
- USB and eSATA connectivity
- Seagate ST3320620AS 3.5 Hard Drive contained within another Vantec USB & eSATA External Case
- USB and eSATA connectivity
When operating either drive over the USB interface, these are the speeds I get (when no other USB device is plugged in).
This is how the 2.5 and 3.5 drives perform when connected via USB.
PCMCIA Specs and eSATA Performance
Now, what the PCMCIA slot has that USB does not: more bandwidth. This decade old technology has been continually improved over the years; today’s slots are 32-bit running at 33MHz for about 132-133MB/s. This is much higher than USB’s maximum speed of 60MB/s, but not quite as fast as the ExpressCard’s available bandwidth. But for a hard drive, it should be reasonably fast right? Let us find out.
Each hard drive can operate much faster now!
As illustrated in the above screen captures, both devices run much faster with less CPU usage. The two drives run at just about the same speed as my internal hard drive, which is more than fast enough for me. CPU usage took about a 7-11% dive.
The most curious thing perhaps is that the 3.5 external drive was running at about the same speed as the 2.5 drive. We all know that 3.5 drives are supposed to be faster, and internal tests done by others indicate the 320GB drive I have should be capable of running at around 70-75MB/s which is well within PCMCIA bandwidth limitations. Clearly, the bottleneck here is the eSATA Card itself. Ideally, PCMCIA can use about 132MB/s. So in practice it will probably yield around 90-100MB/s. It appears that the eSATA Card equally distributes the available bandwidth to each port regardless of whether a drive is attached or what amount of bandwidth it needs. Still, 50MB/s is nothing to complain about.
Additionally, the burst rates for the drives do seem to indicate that in specific circumstances each drive can perform a little bit faster, so the eSATA card can be pushed a little further for short periods of time.
So what happens when you run both drives at the same time? If you have both drives attached, but only run a test on one or the other drive at any given time, you will get about the same performance with regards to speed and access times. However, if you run HDTune tests on both drives at the same time, you get a slightly different story.
Wow!! (view large image)
These two tests were started at about the exact time, and the picture shows it all. Somehow, somewhere, there is a bottleneck that the card has to deal with. Be in drivers or hardware, both drives run at sub-par speeds but they are still faster than USB. In burst mode, which both drives did at the same time, you can easily top out the PCMCIA bandwidth…but during all the other portions of the tests the drives were limited to a combined transfer rate of about 70-75MB/s. Clearly, some software processing overhead is at work here and is likely some type of latency effect as the card switches between controlling each hard drive. The telling clue about this is as one drive’s bandwidth declined, the other one’s rose by about the same margin. CPU usage seems to be about right at 15% to run both drives (remember, each drive was using around 6-7% earlier), so once again the card appears to be a bottleneck.
Performance Summary and Conclusion
A lot of information deserves a table, so here is a complete breakdown of how these devices perform in any given condition.
Clearly, the Vantec eSATA PCMCIA card will provide much better performance than the same USB solution. While the PCMCIA bus is not as fast as the ExpressCard bus, this card certainly does the best that it can with the bandwidth it has and consistently outperforms USB in any situation. The only downside is that performance will not be optimal when running two drives at the same time.
- Allows for MUCH faster data transfer rates than most other solutions (USB, FW400, FW800)
- Lower CPU usage during HDD use.
- Supports two eSATA external drives (think software based RAID!!!).
- Bottleneck of about 50MB/s when using one drive.
- Bottleneck limiting total transfer of around 70-80MB/s when using two drives simultaneously, but burst mode speeds seem to approach PCMCIA bandwidth limits.
- Unconfirmed capability with Vista.
Leave a Reply
You must be logged in to post a comment.