I am trying to connect a Dell 27" U2713H to an XPS 13 L322X and it doesn't work using a mini-DP to DP cord.
The first time it crashed my computer. After that it just flickers and during the first couple of flickers I can see some misshapen version of my desktop on the external monitor for a less than a second, and then it's just black. The laptop's monitor is black the whole time. Then the external monitor goes to sleep saying that it has no signal, the laptop stays black until I unplug the miniDP. Complete failure.
I have updated my video card drivers and installed the "optional" monitor drivers, and the same thing happens. It should work, but it does not.
I connected a Wacom 13HD tablet using a miniDP to HDMI connector and it works with no problem, so the port is not defective. The cable worked with my previous computer, and I tried two different cables with the same results, so it's not the cable.
The first question is whether the graphics card in the XPS13 L322X (the intel HD graphics 4000) actually has the power to drive that monitor. The above poster Dell-Justin doesn't seem to know that the graphics card, rather than the port, is what may be limiting the resolution. Maybe the computer is not configured to use mini-DP to DP (although that should be documented somewhere up front because that's a stupid limitation).
I don't expect anybody from Dell to actually read this, or respond, or actually address the problem if they do respond. Hopefully a power user who has encountered this problem and fixed it can help.