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April 3rd, 2026 06:39
Connecting a Latitude 7450 laptop to S3423DWC by USB-C
I have a Latitude 7450 laptop from work, and have just bought a second-hand S3423DWC monitor which didn't come with a USB-C cable. Connecting the laptop and monitor with an HDMI cable works fine, but when I grabbed a random USB-C cable from around the house, the monitor couldn't detect any video sources.
Am I likely to have more success if I buy a USB-C cable sold as supporting Display-Port 1.2? Do I need a driver on the laptop (Windows 11)?
anne_droid
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April 3rd, 2026 09:54
Hi
My first thought was a cable problem, and the internet doesn't contradict me..........
Connecting a Dell Latitude 7450 laptop to the Dell S3423DWC monitor via USB-C is straightforward using a single USB-C cable, as both devices support DisplayPort Alt Mode, Power Delivery, and data transfer. The Latitude 7450's Thunderbolt 4 USB-C ports fully support this connection to the monitor's USB-C input (up to 3440x1440 resolution at 100Hz), delivering video, peripherals, and up to 90W charging to the laptop.
Requirements
Use the USB-C cable included with the S3423DWC monitor (supports video, data, and 90W PD).
Dell 1.8m USB-C to USB-C Cable (CPL-9W8K8): Matches exact specs with PD, data, and video support; available directly from Dell UK.
Dell USB-C to USB-C (various lengths): Options with 100W PD, 10Gbps data, and 4K DisplayPort video; check dell.com/en-uk for stock.
Longer variants like 4m USB-C (AD340645): 100W PD and data, ideal if needed.
Ensure your Latitude 7450 BIOS and display drivers (Intel Iris Xe or discrete GPU) are updated via Dell SupportAssist or dell.com/support.
No additional adapters or power sources needed for basic video output.
This setup example shows a Dell laptop connected to an external monitor via USB-C, mirroring the single-cable docking capability of the Latitude 7450 and S3423DWC.
Connection Steps
Power off both the laptop and monitor.
Locate a Thunderbolt 4 USB-C port on the Latitude 7450 (typically two on the sides, marked with lightning bolt icon).
Plug one end of the USB-C cable into the laptop's USB-C port and the other into the S3423DWC's USB-C upstream port (labeled for video/data/PD).
Power on the monitor first (OSD button 5), then the laptop; select the USB-C input source using monitor OSD button 2 if needed.
Windows should auto-detect the display; extend or duplicate via Windows Settings > System > Display.
Troubleshooting
No signal: Cycle power on monitor (wait 10s between off/on), check cable seating, or set lower resolution (e.g., 1920x1080) temporarily in Display Settings.
USB ports on monitor inactive: Ensure stable USB-C connection; restart laptop after powering monitor.
Resolution issues: S3423DWC supports up to 3440x1440@100Hz via USB-C; update Intel Graphics drivers if black screen occurs at high res.
Test with another USB-C cable if issues persist; avoid USB-C hubs initially.
Martin Bonner
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April 3rd, 2026 15:05
Brilliant! Thank you. My first action will be to try powering everything down before connecting the random cable. If that doesn't work, I'll order a cable on Tuesday (after the Easter holiday). I will respond with the results.
Martin Bonner
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April 8th, 2026 05:30
So, powering down before connecting didn't help. I did notice that the laptop was charging from the monitor, so it must be the cable.
anne_droid
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April 8th, 2026 08:22
NB: — some USB-C cables are effectively underfeatured: they may support charging only, low power only, or USB 2.0 data only, even though the connector looks the same. A cable can also fail to negotiate enough power for fast charging, so a device may charge slowly, not at all, or only work with certain chargers.
USB-C is just the connector shape; the internal wiring and electronics can vary a lot. Some cables lack the conductors needed for higher data speeds or video output, and some are not built for higher-wattage USB Power Delivery, which is why two identical-looking cables can behave very differently.
A basic USB-C cable may omit pins/wires needed for:
High-speed data.
Video output.
Higher-power charging.
Proper USB Power Delivery negotiation.