HDMI, DisplayPort or USB-C - Which Port Does Your Monitor Need?
Last verified: October 2026
How to read the ports on your computer and screen and pick the single cable that connects them — plus the one tricky thing about USB-C. Rather have a hand? Call (330) 200-8042.
Which Monitor Cable You Need, at a Glance
The wall of ports on a computer puts a lot of folks off, but there are really only three common shapes to know: HDMI, DisplayPort, and USB-C. This guide shows you what each looks like, explains why USB-C is only a plug shape that may or may not carry a picture, and helps you decide whether you need one simple cable or a small adapter. The foolproof shortcut, if the names swim together, is to photograph both ends and match the shapes. There's a printable 29-page version up top.
Common Questions
1 How do I tell HDMI and DisplayPort apart?
Look at the slot's corners. HDMI has both bottom corners clipped and looks symmetrical; DisplayPort has only one corner clipped and looks a little lopsided. That's the quickest way to spot the difference.
2 My laptop only has USB-C. Can it run a monitor?
Often, but not always. USB-C is only a plug shape, and not every USB-C port sends a picture. Check your laptop maker's spec page, or look for a lightning-bolt (Thunderbolt) mark, which reliably carries video.
3 Do I need a cable or an adapter?
If both ends share a shape, one simple cable does it. If the shapes differ — say USB-C on the computer and HDMI on the screen — a small adapter bridges them. A single matching cable is always the tidiest choice.
4 My old monitor uses VGA. Will a cheap adapter work?
Usually not. VGA is an older, different kind of signal, so it typically needs an active converter rather than a plain passive adapter. Our legacy-ports guide covers VGA and DVI in full.
5 Does the video cable carry sound too?
Yes — HDMI, DisplayPort, and video-capable USB-C can all carry sound along with the picture. If your monitor has speakers, sound may start coming from the screen; you can switch it back to the computer's speakers in the sound settings.
6 I plugged in but the screen is black. Why?
Most often the monitor is on the wrong input — press its 'input' or 'source' button. Also check the cable is fully seated, confirm any USB-C port actually carries video, and try 'detect displays' in your computer's settings.
Would You Rather I Just Help?
Ports and cables trip up more people than almost anything else about a new screen — and it's one of the easiest things for me to sort out. Send me a photo of both ends and I'll name the exact cable or adapter to buy, so it works the first time, with nothing to sell you. $99 flat for a visit, or often $49 right on your screen, 30-day come-back-free.
Would you rather I just do this for you?
No shame in it — plenty of folks would rather hand it off, and that's what I'm here for. I'll come to your home, set it up right, and make sure it's working before I leave. Flat $99 per visit — no jargon, no upsell, and every visit is 30-day come-back-free.
Not a hardware job? I can often fix it remotely for $49 — a secure screen-share, up to 2 hours, that you watch the whole time and can end whenever (included free for $39/mo Support Plan members, and it counts toward the $99 if it turns out I need to come out).