// THE EASY OWNER’S GUIDE
Your Dell Latitude 3520, made simple
Every port explained with an interactive tour, three ways to power it — at home, the one-cable desk, and the efficient 12V USB-C trick for vans and off-grid — plus battery care, shortcuts and quick fixes. No jargon, promise.
Rated 4.9 on GoogleFamily-run since 1995 · real people, no call centre// KNOW YOUR PORTS
Every port, explained
Tap any port to see what it does — or press Play tour and let the guide walk you round the machine.
◀ Left side
Right side ▶
Every port at a glance
| Port | Where | What it’s for |
|---|---|---|
| Power in (round barrel) | Left | The supplied Dell 65W charger — the USB-C port charges it too |
| HDMI | Left | A second screen, TV or projector — press Win+P to arrange |
| USB-A 3.2 (the fast one) | Left | Memory sticks, external drives and hubs — use it for moving files |
| USB-C (do-everything) | Left | Charges the laptop, drives a monitor and runs a dock — one cable for everything |
| microSD reader (some models) | Right | Copy photos off a camera or phone memory card |
| Headset jack (3.5mm) | Right | Headphones or a headset with mic |
| USB-A 2.0 (the steady one) | Right | Mouse, keyboard dongle or printer — things that stay plugged in |
| Wired network (RJ-45) | Right | Straight into the router — the most stable connection there is |
| Security lock slot | Right | Takes a laptop cable lock |
Layout is approximate and the exact port mix can vary slightly between configurations — but if the port’s on your machine, this is what it does.
// THREE WAYS TO POWER IT
Home, desk & off-grid power
The Latitude 3520 charges through its barrel jack or its USB-C port — and choosing the right one saves faff at a desk and real battery power off-grid.
| Setup | How | Why |
|---|---|---|
| At home | The supplied 65W charger (barrel or USB-C) | Simple — both fully charge it |
| Business desk | One USB-C dock or a USB-C monitor | One cable carries power, screens, wired network and accessories |
| Off-grid / van | A 65W USB-C PD adapter in a 12V socket (skip the inverter) | Roughly 90%+ efficient and silent — the most efficient way to run off-grid |
// BATTERY CARE
Make the battery last years
The 20–80 sweet spot
Batteries age fastest living at 100% or flat. Mostly plugged in? Set a charge limit around 80% in Dell Power Manager — we preset this on machines we supply.
Heat is the enemy
Don’t leave it in direct sun or a hot parked van — heat ages the battery more than use does. Charge it somewhere ventilated.
Storing it a while?
Leave it around half charged and powered off — not full, not flat. Top it up every couple of months.
On battery out and about
Lower the screen brightness (F6) and use the Balanced power mode — the two biggest levers for making a charge last.
// THE KEYS WORTH KNOWING
Function keys & shortcuts
F1 – F3 · Sound
Mute, volume down, volume up. If sound ‘stops working’, check F1 first — it usually did it.
F4 · Play/Pause
Pauses and restarts music or video. To mute your microphone on a call, use the mic button in Teams, Zoom or WhatsApp.
F8 · Second screen
Same as Win+P: choose Duplicate or Extend when a monitor, TV or projector is plugged in.
F6 / F7 · Brightness
Screen brightness down / up — the biggest battery lever there is.
Fn + Esc · Fn lock
Swaps whether the F-keys do the icons or classic F1–F12 — if your F-keys ‘stopped working’, this got pressed.
Win + L · Lock it
Walking away? Win+L locks the screen instantly. Win+P = screens, Win+V = clipboard history — the three worth memorising.
Exact key layouts can vary slightly between configurations — the icons on the keys themselves are the truth.
// 60-SECOND FIXES
When something misbehaves
Frozen or won’t wake
Hold the power button for 15 seconds, let go, press it once. Fixes a remarkable amount.
No sound
F1 (mute) first, then click the speaker icon and check the right output is selected — plugged-in headphones steal the sound.
Monitor not showing
Press Win+P and pick Duplicate or Extend. Check both cable ends. Still nothing? Try the other video port.
Wi-Fi being moody
Restart the router first (honestly), or plug into it with a network cable — the RJ-45 port needs no setup.
Running slow
If it’s gradual, it’s software clutter — that’s a tune-up, not a new laptop. Run our free PC Benchmark and see.
Anything else
That’s literally us. Remote support, usually within minutes — how it works.
// GOOD QUESTIONS
Frequently asked
Can I charge the Latitude 3520 through USB-C?
Yes — alongside the round barrel charger, the USB-C port takes USB-C Power Delivery. A 65W PD charger gives full-speed charging; 45W charges more slowly (fine overnight); weak phone chargers may only trickle or prompt a warning. One port, one cable, done.
Can I run it in my campervan without an inverter?
That’s the trick this guide is built around: a quality 65W USB-C PD adapter in a 12V socket powers the laptop directly at roughly 90%+ efficiency — silent, no inverter idle drain, and noticeably more runtime from your leisure battery than the 12V→230V→charger route. Pair it with a proper 100W-rated (5A) cable.
Can the USB-C port drive a monitor too?
Yes — it carries DisplayPort video as well as power and data. A USB-C dock or USB-C monitor gives you the one-cable desk: power, screens, wired network and accessories through a single plug.
How do I make the battery last years?
Heat and living at 100% are what age batteries. Keep it out of direct sun (especially in a van), and if it’s plugged in most of the time, set a charge limit (around 80%) in Dell Power Manager — we set this up on the machines we supply. Storing it for a while? Leave it around half charged.
Is this the laptop 365 Techies sells?
Yes — the Latitude 3520 is typical of the refurbished business-grade Dell laptops we supply from £510: tested, securely wiped, fitted with a new 1TB Samsung 990 PRO SSD and covered by our own 5-year guarantee on a 365 support plan. This guide comes free with every one. See refurbished Dells.
Something’s not working — what now?
Try the quick fixes above first (Win+P for screens, the F1 mute key for sound, hold the power button 15 seconds for a frozen machine). Still stuck? That’s literally what we do — remote support, usually within minutes.
// FREE TOOLS
Free tools for your machine
No sign-up, no catch — free tools built by our techies. See all our free tools →
Free tool
365 PC Manager app
365 PC Manager — our free little Windows app. An honest PC health check — health score, one-tap boost, no fake errors — from real local techies. Digitally signed, it installs in a couple of clicks and uninstalls just as easily.
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PC Hardware Checker
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PC Benchmark
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IT Health Check Tool
Get an instant IT & security score out of 100, plus a plain-English action plan.
Try it →This guide comes with the laptops we sell
Refurbished business-grade Dell — Latitude laptops from £510 (with a new 1TB Samsung 990 PRO), OptiPlex desktops from £545 — tested, securely wiped, 5-year guarantee (with a support plan), and set up ready to use. Plus a friendly techie on the end of the phone.
01202 775566 · help@365techies.co.uk · MON–FRI 9AM–5PM