Review on 🚫 GMYLE ExpressCard, USB 3.0 Dual Port Adapter - 34mm Size, Not Compatible with Mac OS by Joshua Romero

I was a little disappointed with it but I think it will work as far as speed goes. I chose two of these for the dual purpose of 1) enabling my two aging laptops to have USB 3 speeds, and 2) performing a dual-port USB 3 disk-to-disk transfer. The first goal was achieved when I easily installed the card in my Inspiron 1545 and Dell m1710 laptops. In testing, data transfer rates ranged from 70 to 80 MB/s using standard hard drives (I don't have SSDs as portable drives yet). I was hoping for a bit more speed - my desktops, which have also recently been upgraded with USB 3 cards, average around 90-100 MB/s. My only guess is that these cards don't offer power options, while on my desktops I had to connect power from the PC PSU to each card. Having said that, I have to note that Ubuntu doesn't require driver installation and speed tests show around 90MB/s, so Windows 7 could be the problem. In any case, I can live with a slightly lower speed on my compared laptops to desktop machines. What is more difficult for me is using both ports of this card to transfer data from USB 3 portable hard drive to hard drive. It was my original intention to get the cards so my laptops could back up and transfer files and share my desktops for general use. However, when I tried to use both ports to transfer data from a 2.5" USB 3 portable hard drive, the power supply was insufficient and one drive froze and rebooted. I was disappointed with this as I didn't think tiny portable drives could cause this problem. So it looks like I can't use the card for the main purpose of a portable drive for data transfer. For the price, I guess I'll keep both as they serve well when doing True Image backups to portable drives (at least I hope they do as I haven't tested this yet. I always do). TI backups from a TI CD outside of Windows (Notify me if the card is not recognized by TI). Just one more issue I forgot to mention. With my Inspiron 1545 I have to be careful when I pull the USB cable out of the card, otherwise the card comes with it. I rarely have this problem on my Dell 1710. Just something to be aware of. UPDATE 12/24/16: I'm reducing my original rating from 3 to 2 stars because one of the modules is now unresponsive (and confirmed it is faulty because I originally bought two and when I replaced it with another one it works other ). I also had an external USB drive damaged because on this laptop (Dell Inspiron 1545) it would eject if I pushed the USB connector too hard into the thing. I will never buy one of these again, neither this type nor the brand.