How does a gaming PC work?

The CPU is the head chef in the kitchen. It runs the game itself (the rules, the physics, every player and enemy) and tells the graphics card what to draw next. The graphics card is the artist who draws every frame you see, many of them every second. For gaming it does most of the work, and the higher your screen's resolution, the more it matters (at 1080p a fast CPU counts for more).

Gaming PC 101

Hi, I'm Justin. I've tested nearly 100 gaming PCs on my YouTube channel, Just!N Tech, and this is the page I wish every parent and first-time PC gamer could read before buying one.

No homework, I promise. Every part gets a sentence or two and an everyday comparison, and the charts use my own FPS numbers.

What each part does

Processor (CPU)
The head chef
The CPU is the head chef in the kitchen. It runs the game itself (the rules, the physics, every player and enemy) and tells the graphics card what to draw next.
Graphics card (GPU)
The artist
The graphics card is the artist who draws every frame you see, many of them every second. For gaming it does most of the work, and the higher your screen's resolution, the more it matters (at 1080p a fast CPU counts for more).
Memory (RAM)
The desk
RAM is desk space: the game keeps what it is using right now on the desk so it can grab it fast. 16GB is the least we'd suggest for gaming today, and 32GB gives you room to spare.
Storage (SSD)
The closet
Storage is the closet where your games are kept when you are not playing them. Today's big games take a lot of room, so a 1TB SSD is a comfortable start; a 500GB one fills up after only a few big games.
Power supply (PSU)
The heart
The power supply is the heart: it pumps power to every other part. A known brand with enough watts for the graphics card keeps everything steady; an unbranded one is a common corner cut.
Cooling
The AC
Cooling is the air conditioning. Fans and coolers carry heat away so the CPU and graphics card can keep running at full speed instead of slowing down to protect themselves.
Case
The house
The case is the house everything lives in. A good one lets plenty of air in and out and has room for a bigger graphics card later.

Video memory: when is 8GB enough?

Video memory (VRAM) is the graphics card's own desk, separate from the PC's RAM. It holds the textures, the detail painted on every wall, face and tree.

8GB is enough at 1080p for most games, including popular ones like Fortnite, Minecraft and Roblox at sensible settings.

At 1440p and 4K with high settings, new big games can need more than 8GB. When a game runs out, it stutters or has to lower its detail. That is why our PC pages flag 8GB of video memory as tight at 1440p and 4K, and never at 1080p.

Playing at 1440p or 4K, or want the PC to last a few years? Pick a graphics card with more than 8GB, like 12GB or 16GB.

CPU or graphics card: which matters more?

It depends on your screen's resolution, how many dots (pixels) make up the picture.

At 1080p each frame is small, so a strong graphics card draws it very fast and often ends up waiting on the CPU. That is where the CPU matters most: a faster CPU gets you more frames.

At 1440p and 4K every frame has many more pixels to draw (4K has four times as many as 1080p), so the graphics card sets the pace and a faster CPU adds little.

So for 1080p, don't pair a big graphics card with a weak CPU. For 1440p and 4K, put more of the budget into the graphics card.

Same graphics card, two CPUs

1080p

Ryzen 7 9800X3D255 FPS Max settings, native

Core Ultra 9 285K177 FPS Max settings, native

Ryzen 7 9800X3D111 FPS Max settings, native

Core Ultra 9 285K111 FPS Max settings, native

The same RTX 5090 graphics card with two different CPUs, in Cyberpunk 2077 at Max settings, native. At 1080p the Ryzen 7 9800X3D gets 78 more FPS than the Core Ultra 9 285K. At 4K both get 111 FPS: the graphics card sets the pace there, not the CPU.Justin's measured FPS, from two Alienware Area-51 PCs he tested.

Same CPU, two graphics cards

1080p

RTX 5090213 FPS Max settings, native

RTX 5080211 FPS Max settings, native

RTX 5090161 FPS Max settings, native

RTX 5080106 FPS Max settings, native

The same Ryzen 7 9800X3D CPU with two different graphics cards, in Call of Duty Black Ops 6 at Max settings, native. At 1080p they are only 2 FPS apart: the CPU holds both cards back there. At 4K the RTX 5090 gets 55 more FPS than the RTX 5080.Justin's measured FPS, from two Corsair Vengeance a7500 PCs he tested.

Every number in these charts is one of Justin's own runs, exactly as he measured it, never an estimate. How we get our numbers.

What monitor do you need?

Resolution is how sharp the picture is: 1080p (Full HD), 1440p (often called QHD) and 4K. A higher resolution looks sharper but needs a much faster graphics card.

Refresh rate, in hertz (Hz), is how many new pictures the monitor can show each second: 60 Hz, 144 Hz, 165 Hz, 240 Hz and up. Higher feels smoother, especially in fast games.

Match the PC to the monitor. A monitor shows at most as many frames a second as its Hz, so a 1080p 144 Hz monitor wants a PC that keeps up with its Hz in your games at 1080p. A PC far faster than a 60 Hz screen still only shows what that screen can.

For most kids and new gamers, a 1080p monitor at 144 Hz or so is a great, affordable match for a budget gaming PC.

Set your monitor once on My Dashboard, and every PC page tells you how many of your games hit its refresh rate. Set my monitor on My Dashboard.

Prebuilt or build it yourself?

A prebuilt arrives ready to plug in, with one warranty for the whole PC and one place to call if something is wrong. It is the easy choice for a gift or a first gaming PC.

Building means buying every part yourself and putting it together. It teaches you a lot and lets you pick every part, but it takes an afternoon or more, and if something doesn't work, you figure out which part.

Building is not always cheaper. Sometimes the same parts cost less on their own; sometimes a prebuilt on sale costs less than its parts.

How to spot a bad deal

8GB of video memory on a PC sold for 1440p or 4K gaming.
One memory stick (like "1x16GB") instead of two: single-channel memory costs FPS in CPU-heavy games.
An unbranded power supply, or one smaller than the graphics card maker recommends.
A 500GB SSD or smaller: room for only a few big games.
No Wi-Fi, if the PC can't sit near your router: you would need a network cable or a Wi-Fi adapter.
A warranty under a year: most prebuilts give at least one.
A last-generation graphics card at a new-generation price.

Every PC page on this site checks these for you and lists them as red flags, from the specs the listing actually states. When a listing doesn't say, we say "not listed" instead of guessing.

Found a PC at a store? Paste its link into Is it a good deal? for a quick check, or compare PCs side by side. Want a laugh? Roast my prebuilt.

What to check on day one

Turn it on the day it arrives (even before you wrap it) and run Windows Update.
Plug the monitor into the graphics card, not the motherboard, and install the latest driver from the graphics card's maker.
Set the monitor's refresh rate in Windows (it often starts at 60 Hz).
Optional: if the memory is rated faster than its default speed, turning on EXPO or XMP in the BIOS runs it at that rated speed. Check the PC brand's warranty terms first. Leaving it off is fine: the PC works either way.
Keep the box and the receipt until the return window ends.

Every step, made for your exact PC: Your first-day setup checklist.

Buying a gaming PC for a kid?

For Fortnite, Roblox and Minecraft at 1080p, you don't need the most expensive PC. Look for a real graphics card (not "integrated graphics"), 16GB of RAM, a 1TB SSD if you can, and a known-brand power supply.

Our gift guides pick in-stock PCs at real store prices we check every morning, and every pick clears our quality bar.

Gaming PC 101

What each part does

Processor (CPU)

Graphics card (GPU)

Memory (RAM)

Storage (SSD)

Power supply (PSU)

Cooling

Case