Can Surface 3 support an external 4K monitor via DP?

[wpcoe]

As part of a troubleshooting effort with a Surface Pro 2017, I attempted to use an external monitor (Dell 2415Q, 24" 4K) using a miniDP-to-DP cable (no separate adapter) with my Surface 3, and it doesn't work: constant flashing before Windows log-on screen appears.

The Intel ARK page for the x7-Z8700 processor doesn't say what the DP capability is for an external monitor. It only says:

• Max Resolution (HDMI 1.4) ‡3840x2160
• Max Resolution (eDP - Integrated Flat Panel) ‡2560x1600

Does the Surface 3 support DP for an external monitor at all? If it does, is the 4K resolution of my Dell monitor throwing it off?

For comparison, the ARK page for i7-7660U says:

• Max Resolution (HDMI 1.4) ‡4096x2304@30Hz
• Max Resolution (DP) ‡4096x2304@60Hz
• Max Resolution (eDP - Integrated Flat Panel) ‡4096x2304@60Hz

 

[GreyFox7]

Hard to track down any information on this... the best I've come up with so far is a paragraph on the Notebookcheck site.
Intel HD Graphics (Cherry Trail) Benchmarks

The Intel HD Graphics GPU in our review sample of the MS Surface 3 (Atom x7-Z8700) only supported DisplayPort 1.1 as it seems, as 4K (3840x2160) with 30 Hz was the maximum Refresh Rate we could achieve.
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[wpcoe]

@GreyFox7 : Thanks for that reference.

Following a link from that notebookcheck.net article I found elaboration on their comment:

4K Video Output via Mini-Displayport
We use an adaptor to attach the Surface 3 to our Asus PB287Q 4K test display (3840x2160 pixels) and check the performance of the video output. We can quickly see that the picture is only running at 30 fps (DisplayPort 1.1), which is noticeable when you move the cursor, for example, which lacks smoothness and precision. It can also be noticeable when you move windows or scroll through websites. Intel’s Update Utility does not find any drivers right now, which could give us extended settings.

It may be significant that they used "an adaptor" of some sort. I'm using the mDP port with a mDP-to-DP cable.