Which connector types should I consider when selecting a graphics card?
I plan to connect two monitors and thought DVI is still current, but seeing HDMI, display port, mini HDMI, and (I think) mini display port.
Modern cards typically have 3 Display Port & 1 HDMI, built-in (on Intel) more commonly 2 HDMI and a Display Port
If you have one 1920x1080 monitor and one PC life is pretty easy - just hook the two together with an appropriate cable.
HDMI and DVI are electrically similar and passive bi-directional adapters easy to find so if your monitor is a bit long in the tooth and only has DVI that just needs a suitable adapter or HDMI<->DVI cable.
Passive display port to HDMI adapters exist but rely on the card (or motherboard) detecting that it is connected to an HDMI port and switching signal standards - so they only work with DP at the computer end and HDMI on the monitor.
If you have a higher resolution display then you need to know that HDMI 1.4 only supports 4k at 30Hz, which is useless for a PC monitor. It's not that much of a problem as a new graphics card will support HDMI 2.0 but it becomes a problem with Intel built-in graphics as they are stuck at HDMI 1.4 - so to drive better than 1920x1080 with Intel built in graphics you need to use Display Port (note that using a passive DP->HDMI adapter does not get round the problem).
Additionally if you use a KVM switch with multiple PCs be aware that DP KVM's are not really a thing (few on the market and all very expensive). So a combination of a high res monitor, KVM switch and Intel built-in graphics can be a headache (guess how I know

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