StarTech.com 2-port DisplayPort KVM Switch with Built-in USB 2.0 Hub - Supports 4K Video Resolution at 30Hz - Ultra HD (SV231DPU2)

I wanted to use this KVM unit to switch between a server with VGA graphics and a desktop with DVI-D graphics (my monitor can automatically handle VGA and DVI-D). Everything works except that the VGA signal never seem to get to a Console port that connects to a display monitor. I had a similar problem with another brand of KVM switch and it seems that mixing VGA and DVI-D is an insurmountable problem in KVM electronics (one would have thought switching analogue VGA signal can be easily done by relay-assisted mechanical switch but doesn't seem that easy).I contacted StarTech technical support and I was more than impressed with the exceptional help provided by very knowledgeable (and should add very courteous) technical staff. You'd feel that they won't let you go off the phone until the problem was solved. In fact, while I was on the phone, one of the technical assistants was testing the very same KVM switch with the setup as I described (live test while on the phone!). They confirmed the exact problem I was having and narrowed down the likely problem to a cable used to split VGA and DVI-D signals on the console port, which is StarTech's own branded cable -  StarTech.com 6ft DVI-I Male to DVI-D Male and HD15 VGA Male Video Splitter Cable . Before I carried out further checks they suggested with the cable after the phone call, an email arrived from StarTech tech support advising me to consider another model No SV231DDVDUA which could do what I wanted without any connector adapters or signal splitter. Typing in the model SV231DDVDUA into Amazon's search revealed the product  StarTech.com 2 Port DVI VGA Dual Monitor KVM Switch with Audio and 2.0 USB Hub  which does precisely what I wanted without any added adapters and signal splitter. This model is nearly £30 more expensive but for my requirement well worth it and looking at the back connectors you'd get some idea why it's more expensive. I immediately placed my order for model SV231DDVDUA and proceeded to making arrangement to return this KVM switch.Just to emphasise a point - compared with my technical support experience elsewhere, I consider StarTech's technical support as if they're going beyond call of duty and they really give a true meaning to what technical support should be. Thank you StartTech!In summary, avoid this KVM switch if you're mixing VGA and digital outputs else all should be alright, say for DVI-D or DVI-I outputs. The only reason for knocking off one star is the lack of information relating to the KVM quirk such as mixing VGA and digital graphics being a potential problem area. I have learnt a lot from the technical support as described above and I'm of the opinion that some warning/alert messages need to go into the user manual as KVM electronics seem to have inherent problems associated with switching protocols that users can easily overlook.

This KVM switch has a much underplayed feature: supporting Displayport MST. This means that you can with this _single_ switch support up to four[1] 1080p displays, using a single set of cables. I have 2 Dell U2414H monitors hooked up to this switch and both my laptop and PC with no extra components.With my old (and far more expensive!) StarTech SV231DPDDUA dual head dual computer displayport kvm switch (pictured), I needed 3 displayport cables for each individual monitor, producing an enormous mess, and I had to use an MST hub to split my graphics card's single DisplayPort output into two.That said, there are downsides. the SVP231DPDDUA can use the keyboard to switch, meaning I can press CTRL-CTRL-1 and CTRL-CTRL-2 to switch between machines, and just hide the switch. You can only do this with this device if you install their awful app, which of course only supports some versions of Windows and MacOS and adds an irremovable green pea icon to your tray. The second downside is that the USB ports are on the front. This means that if you put it on your desk, there's a mess of cables in front of it where your keyboard and mouse cables are bunched up in front of it.Overall, supporting MST is a huge boon, enough for me to give this a nearly perfect score. I feel like STARTECH might be downplaying the importance of supporting MST because, honestly who is going to buy a 4 port KVM for £500 when you can buy this for ~£95 and have eleven less cables to plug in? Other than MST support, this product is mostly a downgrade from the fairly old SV231DPDDUA, and the newer SV231DPU3A (which supports USB 3.0 and is a much more attractive device, though it only works if you use one monitor since there's no MST).PROS:- Supports MST / Daisychain!- Much, much cheaper than KVMs which do similar thingsCONS:- It lost hardware keyboard switching support; need to install an app- USB on the front which makes for bad desk cable management- It's fairly ugly compared to some of their other new switches- No sound- No USB 3I've attached a picture of my setup as of now. Pictured is my old KVM. The new one is under the desk.On daisychain support:- you must have a newish graphics card, see [1]- you must have monitor(s) supporting daisy chaining- MacOS appears to have daisychain disabled except for on apple made monitors, to stifle the competition[1][...]

Having used VGA KVMs for years, I decided that I really needed to upgrade, particularly now that I have a 4K monitor. Could not believe how expensive the DVI/HDMI/Displayport KVMs are and could never justify spending the 300GBP+ that appeared to be the mark for a Displayport one.Could also not understand why Startech do this one but their full size displayport one cannot handle 4K60Hz.Checked with them that this should work via displayport to mini-displayport cables and they confirmed it should be OK.The 1m Startech cables I bought worked great but I needed one to be a bit longer and bought their 2m one which had issues. A UGreen 2m one worked fine however.This setup works really well switching between my main PC and my work laptop.However, there is an issue (common to most Displayport KVMs) that prevents me giving it 5 stars.Basically these devices do not work like the VGA ones in that they physically disconnect the display. This causes screens to be reorganised as they disconnect and reconnect.I did discover a workaround to this however.On my PC, I take a DVI output to one of the HDMI inputs on my monitor and duplicate the screen on DVI and Displayport. The DVI one only works at 30Hz, but it's enough to keep the display alive at the same resolution.I do a similar thing on my laptop by taking a 2nd video output to a 4K HDMI headless ghost.Displayport disconnection still occurs on switching but the as far as Windows is concerned, it's the same output, just to a single or two duplicated displays. This prevents the windows from rearranging and keeps everything as it should be.So the end result is that I am switching successfully between 3840x2160 @ 60Hz on my PC and 2560x1440 @ 60Hz on my laptop