The compression also caused a subtle but noticeable delay in the screen response, but it’s still absolutely usable for browsing, programming and other day-to-day productivity. When using the USB2HDMI adapter the aforementioned necessary compression was noticeable and is not dissimilar to the sort you’d see in compressed JPEG images.
Tearing was even more prominent in full screen video on OSX, and this wasn’t something I could find a fix for. Windowed video isn’t quite as bad as full-screen, however I noticed some tearing- a visual artifact that appears when the video refresh rate and the screen refresh rate are at odds with each other. It’s simply not as good as a native HDMI connection. This is not a use I’d strongly recommend the USB2HDMI for, however, despite it being the most obvious. Ultimately you’re only going to need to use these settings if you plan on a bit of video watching on a TV using the HDMI adaptor. This “Optimize for Video” option isn’t available on the Mac at all, so choppy video is the norm. On Windows, a WEI score of 4.5 or better is recommended, and the checking of the “Optimize for Video” setting in the GUI is required for full screen video playback. There’s some respite for Windows users, however. Video will always be a little choppy, and thus is best watched on a “native” display connected via VGA/DVI/HDMI/DisplayPort or otherwise. This is not much of an issue, however, as playing video via the DisplayLink display isn’t exactly the best of experiences anyway. User-level CPU use (OSX) is dramatically higher when playing a youtube video on the DisplayLink display, versus a native display. Compression is used, and thus a higher CPU/GPU load is incurred when using a DisplayLink device.
USB doesn’t natively have the bandwidth for full-screen displays, this is well known and documented by DisplayLink.
It also has built-in sound so you can get both your sound and picture through the HDMI cable, an absolute must if you plan on using it for movie watching.
It uses HDMI for the video connection, which is very easily adapted into DVI using an HDMI->DVI cable. Although your mileage may vary getting it up and running with Linux.
The latter, the USB2HDMI, is compatible with Mac OS X, Windows and Linux. This is par for the course, naturally, as both devices squeeze a video signal through USB using compression, and both devices therefore have delay. In fact, I found it almost good enough to play games via, but it was just little bit sluggish to best a good ol’ directly connected monitor. The USB2HDMI adaptor may require two USB ports, but it produces a much more responsive picture and goes up to 1920×1080 resolution providing your computer will support it. Let me come right out and say that the latter is better. They are the Startech USB2DVIE2 and the Startech USB2HDMI. USB to video adaptors have been on my to-do list for a while, and I’ve finally got ’round to getting my hands on a couple.