How to Buy an All-in-One Desktop PC: Buyer’s Guide

Short answer: buy the largest screen your desk depth can support at a comfortable viewing distance, then make sure the panel gives you at least roughly 110 pixels per inch — which means 2560×1440 at 27 inches, not 1920×1080 — and only after that decide whether you need upgradeable memory and storage or a discrete mobile GPU. For most office and light-gaming buyers in 2026, a 27-inch 1440p IPS all-in-one with two SO-DIMM slots, two M.2 slots and an HDMI-in port is the best long-term buy. If you want 1440p high-refresh gaming inside an AIO chassis, you are shopping a small, expensive class that uses laptop-class graphics silicon, and the price jump is steep.

Quick comparison: five AIO classes worth shortlisting

The picks in detail

Best overall: 27-inch 1440p IPS all-in-one with upgradeable RAM and storage

This is the class that gets the fundamentals right. The panel is big enough that 1440p lands at ~109 PPI, the chassis is deep enough that a 27-inch board can carry two SO-DIMM slots and two M.2 2280 slots, and the port cluster usually includes HDMI-in so the screen survives the computer. Who it suits: anyone replacing a tower-plus-monitor setup who expects to keep the machine five years and add 32 GB and a second SSD in year three. Main trade-off: it is the least glamorous AIO you can buy, and the 65 W CPU class means sustained all-core workloads (video export, code compilation) run noticeably slower than a desktop tower with the same chip name.

Best budget: 23.8-inch 1080p touch all-in-one

At 23.8 inches, 1920×1080 works out to roughly 92 PPI, which is acceptable at a 20–24 inch viewing distance and noticeably soft if you sit further back. Who it suits: office work, browsing, video calls, schoolwork, and anyone who wants a single cable to the wall. Main trade-off: memory is almost always soldered LPDDR5X and the single M.2 slot is often 2230 rather than 2280, so buy 16 GB and 512 GB on day one — you cannot fix either later.

Best for small desks and creative work: 24-inch iMac (M-series)

Per Apple’s published spec sheet, the 24-inch iMac’s 4480×2520 panel works out to roughly 218 PPI, which is why text looks like a printed page at normal desk distance. Who it suits: writers, designers, and anyone with a shallow desk who wants the whole computer to disappear. Main trade-off: unified memory is fixed at purchase and there is no video input, so when the internals age out, the panel goes with them. Buy 24 GB or more up front if you plan to keep it.

Best gaming-capable AIO: 27–34-inch model with a discrete mobile GPU

True gaming all-in-ones are rare and use laptop silicon — an RTX 4050/4060-tier part at 60–115 W — because there is no room for a full desktop card and its cooling. Who it suits: buyers who want one machine for 1440p gaming and desk work and will not accept a tower. Main trade-off: you pay a large premium over a tower with the same GPU, you cannot upgrade the graphics later, and thermals under sustained load are the weak point. Expect roughly 60–100 FPS in mainstream titles at 1440p high settings, varying widely with the specific title, patch, CPU and upscaling settings.

Best for shared or kitchen use: portable 23.8-inch AIO with a battery

HP’s Envy Move line established this class: a 23.8-inch 1440p touchscreen AIO with a handle and an internal battery rated for several hours. Who it suits: households that move one computer between kitchen, dining table and spare room. Main trade-off: battery capacity and thermals limit sustained performance, and the panel is glossy and touch-coated, which shows fingerprints.

How to choose: the numbers that actually matter

Size the screen to your desk depth, not your budget

Ergonomic guidance puts comfortable desk viewing distance at roughly 20–30 inches. A 27-inch 16:9 panel is about 23.5 inches wide and 13.2 inches tall, so it fills that range nicely and wants about 24–30 inches of eye-to-screen distance. A 34-inch 21:9 ultrawide is the same height as a 27-inch 16:9 (about 13.1 inches) but roughly 31.4 inches wide — it consumes desk width, not depth. If your desk is under 24 inches deep, a 23.8–24-inch screen is the honest answer, and a 27-inch will sit too close and force your eyes to track across a wide arc.

Panel type: IPS, VA or OLED

IPS is the default for AIOs and the right one: stable colour at angles, no smearing, 99% sRGB typical. VA gives deeper blacks but visible dark-scene smearing on a desktop UI. OLED looks superb but an all-in-one runs a static taskbar, static dock and static window chrome for eight hours a day, which is the worst-case burn-in pattern — if you buy OLED, set the taskbar to auto-hide, enable a screensaver after 5 minutes, and lower peak brightness for document work.

Upgradeability: check three things before you pay

• Memory type: soldered LPDDR5X runs at 7500–8533 MT/s and cannot be changed; SO-DIMM DDR5 slots typically run at 4800–5600 MT/s but let you move from 16 GB to 64 GB for roughly $120–$200 in parts. On a 27-inch chassis, the slots are usually behind one rear panel.
• M.2 form factor and slot count: 2280 is the standard, widely available length; 2230 drives cost more per terabyte and are far less common. Two slots let you add storage instead of cloning and swapping.
• Interface generation: PCIe 4.0 ×4 tops out around 7.9 GB/s and real drives deliver 5,000–7,400 MB/s; PCIe 5.0 ×4 doubles the ceiling but matters little for office work.

Ports: work out the video bandwidth you need

An 8-bit RGB signal needs pixels × 24 bits × refresh rate. Add roughly 20% for blanking overhead and you get the on-wire rate.

Practical read: a USB-C port in DP Alt Mode is fine for a single 4K60 external monitor; for 4K120 or dual 1440p you want Thunderbolt 4 (40 Gbps, ~25.9 Gbps of tunnelled DisplayPort) or Thunderbolt 5, which raises the ceiling substantially. Also count USB-A ports — AIOs often ship with two at the rear and none at the side, which is miserable for a flash drive.

Power budget: the number nobody prints on the box

Add it up for a mid-range AIO: a 65 W CPU class can spike to 90–120 W on boost, a laptop-class discrete GPU draws 60–115 W, the panel adds 25–40 W, and board, storage and fans add 15–25 W. Worst case is roughly 185–300 W. Any AIO in that configuration shipping with a 120 W or 150 W external adapter will throttle the moment CPU and GPU load overlap; look for 230 W and up. An office-only AIO with integrated graphics idles around 25–40 W and peaks near 90 W, so a 120–150 W brick is genuinely fine there.

Decision matrix

Frequently Asked Questions

Can you upgrade the RAM in an all-in-one PC?

Sometimes, and it depends entirely on the chassis size. Many 24-inch AIOs solder LPDDR5X to the board, which means the memory you buy is the memory you keep forever. Most 27-inch AIOs and larger use two SO-DIMM slots reachable behind a single rear access panel, so a 16 GB machine can become 32 GB or 64 GB later. Check the manufacturer’s spec sheet for the words “SO-DIMM” or “upgradeable memory” before you buy — if you see “LPDDR5X” with no slot count, assume it is fixed.

Is an all-in-one good for gaming?

Only specific models. The AIOs that game well use laptop-class discrete GPUs in the RTX 4050/4060 tier and ship with 230 W or larger external power supplies; everything else runs integrated graphics that handle esports and older titles at 1080p and little more. If gaming is the primary use, a tower plus a separate monitor gives you a faster GPU for the same money and lets you upgrade it later. If you want one box and accept the premium, buy the discrete-GPU AIO and nothing less.

Do all-in-ones have HDMI-in so the screen can be used as a monitor?

No, and this is the single most overlooked specification in the category. HDMI-in lets you plug a console, laptop or future mini PC into the AIO’s panel, which extends the display’s life well past the computer inside it. Several 27-inch Windows AIOs include it; Apple’s 24-inch iMac has no video input at all. If you expect to keep the machine five or more years, an HDMI-in port is worth more than an extra 8 GB of memory.

Is OLED a good choice for an all-in-one used for work?

It is a risk rather than a rule. OLED delivers excellent contrast and near-instant pixel response, but a desktop is a static-image workload: taskbar, dock, window borders and spreadsheet grids sit in the same pixels for hours. If you buy OLED, auto-hide the taskbar, set a screensaver at 5 minutes, and avoid maximum brightness for documents. If the machine will be a general-purpose family computer, an IPS panel is the lower-stress choice.

How much RAM and storage should I buy in an all-in-one?

For Windows office work in 2026, 16 GB is the floor and 32 GB is comfortable if you keep many browser tabs and run virtual machines or large spreadsheets. For creative work, 32 GB is the realistic minimum. On storage, 512 GB is the entry point and 1 TB is the sensible target, because AIO M.2 slots are sometimes 2230-length and single, which makes later upgrades awkward and pricier per terabyte.

Is an all-in-one worse than a desktop tower plus a monitor?

It is worse at thermals, repairability and price-per-performance, and better at cable count, footprint and industrial design. A tower with the same CPU and GPU will run cooler, quieter and cheaper, and you can replace the monitor or the graphics card independently. Buy the AIO when desk space and visual tidiness genuinely matter to you, and buy the tower when sustained performance and future upgrades do.