Buying Guide

The Best CPUs Under $400

Eight processors priced under $400 at the time of writing, compared on cache, cores, boost clock and platform.

By The PC Journal editorial team

13 min read8 products evaluated

Under $400 the choice splits between gaming cache and core count. AMD's X3D chips lead for games; twelve- and twenty-core chips lead for work.

We compared eight processors on cache, cores, boost clock and platform, using manufacturer specifications.

Quick Picks

Our 8 recommendations at a glance. Tap a pick for the full verdict.

  1. Best for Gaming Under $400

    AMD Ryzen 7 7800X3D

    96MB of L3 on eight cores.

    Best for: Gaming-first builds.

    Our take Check price for AMD Ryzen 7 7800X3D (opens in a new tab)

  2. Best Efficient Pick

    AMD Ryzen 7 9700X

    Eight Zen 5 cores at 65W.

    Best for: Quiet, cool builds.

    Our take Check price for AMD Ryzen 7 9700X (opens in a new tab)

  3. Best for Work

    AMD Ryzen 9 9900X

    Twelve Zen 5 cores.

    Best for: Rendering and compiling.

    Our take Check price for AMD Ryzen 9 9900X (opens in a new tab)

  4. Best Intel Pick

    Intel Core Ultra 7 265K

    Twenty cores on LGA1851.

    Best for: Intel creator builds.

    Our take Check price for Intel Core Ultra 7 265K (opens in a new tab)

  5. Well-Rounded Choice

    Intel Core i7-14700K

    The Core i7-14700K has twenty cores on LGA1700 and supports DDR4 or DDR5.

    Best for: Buyers who want 5.6ghz maximum boost.

    Our take Check price for Intel Core i7-14700K (opens in a new tab)

  6. Best AM4 Upgrade

    AMD Ryzen 7 5800X3D

    96MB of L3 on AM4.

    Best for: Keeping an AM4 board.

    Our take Check price for AMD Ryzen 7 5800X3D (opens in a new tab)

  7. Solid Alternative

    AMD Ryzen 9 7900X

    The Ryzen 9 7900X offers twelve Zen 4 cores at a lower price than the 9900X.

    Best for: Buyers who want 64mb of l3 cache.

    Our take Check price for AMD Ryzen 9 7900X (opens in a new tab)

  8. Worth Considering

    Intel Core i5-13600K

    The Core i5-13600K is the previous-generation fourteen-core LGA1700 chip.

    Best for: Buyers who want 14 cores for encoding and background work.

    Our take Check price for Intel Core i5-13600K (opens in a new tab)

Our Picks

AMD Ryzen 7 7800X3D

Best for Gaming Under $4001 of 8

AMD Ryzen 7 7800X3D on Amazon (opens in a new tab)

The Ryzen 7 7800X3D was the first eight-core AM5 chip with 3D V-Cache.

Best for

Gaming-first builds.

Skip if

Pass on it if no cooler in the bo rules it out for your setup.

Why we like it

It carries the same 96MB of L3 as the 9800X3D at a lower boost clock and a lower price. On boost clock it sits mid-pack at 5GHz: the Ryzen 9 9900X offers 5.6GHz, and the Ryzen 7 5800X3D comes in at 4.5GHz. It matches the Ryzen 7 9700X and the Ryzen 7 5800X3D on core count (8 cores).

It matches the Ryzen 9 9900X on rated power (120W). It also offers the Zen 4 architecture. It needs an AM5 board (A620, B650, B850, X670 or X870 series) and DDR5 memory; check the board's CPU support list for the minimum BIOS version.

Budget for a dual-tower air cooler or a 240mm-plus AIO, since none is included. Its price falls between the Core i5-13600K and the Core Ultra 7 265K, based on our last check.

Key dimensions & specs

  • L3 cache: 96MB
  • Max boost: 5GHz
  • Cores / threads: 8 cores
  • Rated power: 120W
  • Threads: 16
  • Socket: AM5
  • Memory: DDR5
  • Cooler in box: No
  • Integrated graphics: Yes

Pros

  • 96MB of L3 cache from 3D V-Cache
  • Integrated graphics for display output without a graphics card
  • First-generation AM5 3D V-Cache
  • The Zen 4 architecture

Cons

  • No cooler in the box
  • Costs more than the Ryzen 9 7900X at the time of writing
AMD Ryzen 7 9700X

Best Efficient Pick2 of 8

AMD Ryzen 7 9700X on Amazon (opens in a new tab)

The Ryzen 7 9700X runs eight Zen 5 cores at a 65W default rating.

Best for

Quiet, cool builds.

Skip if

Look at the others if this bothers you: no cooler in the box.

Why we like it

It needs only a modest cooler and has room to grow with AMD's power boost setting. On L3 cache it sits mid-pack at 32MB: the Ryzen 7 7800X3D offers 96MB, and the Core i5-13600K comes in at 24MB. On boost clock it ties with the Core Ultra 7 265K at 5.5GHz.

On rated power it leads this guide at 65W, ahead of the Ryzen 7 5800X3D (105W). It needs an AM5 board (A620, B650, B850, X670 or X870 series) and DDR5 memory; a 600-series board may need a BIOS update first, so check the maker's CPU support list for the minimum version. No cooler is included; a single-tower air cooler is enough at its rating. Its price falls between the Ryzen 9 9900X and the Core i5-13600K, based on our last check.

Key dimensions & specs

  • L3 cache: 32MB
  • Max boost: 5.5GHz
  • Cores / threads: 8 cores
  • Rated power: 65W
  • Threads: 16
  • Socket: AM5
  • Memory: DDR5
  • Cooler in box: No
  • Integrated graphics: Yes

Pros

  • 5.5GHz maximum boost
  • 65W rating suits a modest air cooler
  • Integrated graphics for display output without a graphics card
  • The Zen 5 architecture

Cons

  • No cooler in the box
  • Costs more than the Ryzen 9 7900X at the time of writing
AMD Ryzen 9 9900X

Best for Work3 of 8

AMD Ryzen 9 9900X on Amazon (opens in a new tab)

The Ryzen 9 9900X has twelve Zen 5 cores for work that scales with threads.

Best for

Rendering and compiling.

Skip if

Skip it if this is a deal-breaker for you: no cooler in the box.

Why we like it

For games alone, the eight-core X3D chips are the better buy. On L3 cache it ties with the Ryzen 9 7900X at 64MB. On boost clock it ties with the Core i7-14700K and the Ryzen 9 7900X at 5.6GHz.

It matches the Ryzen 9 7900X on core count (12 cores). It matches the Ryzen 7 7800X3D on rated power (120W). You also get the Zen 5 architecture.

It needs an AM5 board (A620, B650, B850, X670 or X870 series) and DDR5 memory; a 600-series board may need a BIOS update first, so check the maker's CPU support list for the minimum version. Budget for a dual-tower air cooler or a 240mm-plus AIO, since none is included. Its price falls between the Ryzen 9 7900X and the Ryzen 7 9700X, based on our last check.

Key dimensions & specs

  • L3 cache: 64MB
  • Max boost: 5.6GHz
  • Cores / threads: 12 cores
  • Rated power: 120W
  • Threads: 24
  • Socket: AM5
  • Memory: DDR5
  • Cooler in box: No
  • Integrated graphics: Yes

Pros

  • 64MB of L3 cache
  • 5.6GHz maximum boost
  • 12 cores for encoding and background work
  • Integrated graphics for display output without a graphics card

Cons

  • No cooler in the box
  • Costs more than the Ryzen 9 7900X at the time of writing
Intel Core Ultra 7 265K

Best Intel Pick4 of 8

Intel Core Ultra 7 265K on Amazon (opens in a new tab)

The Core Ultra 7 265K uses Intel's LGA1851 platform with twenty cores.

Best for

Intel creator builds.

Skip if

Worth skipping when no cooler in the bo is a problem.

Why we like it

It is strong in multi-threaded work and supports only DDR5. Its 30MB L3 cache ranks 7th of 8 here, behind the Ryzen 7 7800X3D (96MB) and ahead of the Core i5-13600K (24MB). It matches the Ryzen 7 9700X on boost clock (5.5GHz).

On core count it ties with the Core i7-14700K at 20 cores. On rated power it ties with the Core i7-14700K and the Core i5-13600K at 125W. It is the only pick here with an LGA1851 socket; the Core i5-13600K has an LGA1700 socket instead.

It also comes with 8 performance and 12 efficient cores and a built-in NPU for AI features. It needs an LGA1851 board (Intel 800-series chipset) and DDR5 memory; LGA1700 boards and coolers without an LGA1851 mounting kit will not fit. When we checked, only the Ryzen 7 7800X3D and cheaper picks cost less, and the Ryzen 7 5800X3D cost more.

Key dimensions & specs

  • L3 cache: 30MB
  • Max boost: 5.5GHz
  • Cores / threads: 20 cores
  • Rated power: 125W
  • Threads: 20
  • Socket: LGA1851
  • Memory: DDR5
  • Cooler in box: No
  • Integrated graphics: Yes

Pros

  • 5.5GHz maximum boost
  • 20 cores for encoding and background work
  • Integrated graphics for display output without a graphics card
  • 8 performance and 12 efficient cores

Cons

  • No cooler in the box
  • Costs more than the Ryzen 9 7900X at the time of writing
Intel Core i7-14700K

Well-Rounded Choice5 of 8

Intel Core i7-14700K on Amazon (opens in a new tab)

The Core i7-14700K has twenty cores on LGA1700 and supports DDR4 or DDR5.

Best for

Buyers who want 5.6ghz maximum boost.

Skip if

Worth skipping when no cooler in the bo is a problem.

Why we like it

It needs strong cooling to hold its boost clocks. Its 33MB L3 cache ranks fifth of 8 here, behind the Ryzen 7 7800X3D (96MB) and ahead of the Core i5-13600K (24MB). It matches the Ryzen 9 9900X and the Ryzen 9 7900X on boost clock (5.6GHz).

On core count it ties with the Core Ultra 7 265K at 20 cores. On rated power it ties with the Core Ultra 7 265K and the Core i5-13600K at 125W. Like the Core i5-13600K, it has an LGA1700 socket, while the Ryzen 7 7800X3D uses an AM5 socket.

Like the Core i5-13600K, it has DDR4 or DDR5 memory, while the Ryzen 7 5800X3D uses DDR4 memory. You also get 8 performance and 12 efficient cores and support for both DDR4 and DDR5 boards. At our last price check it topped the group, with the Ryzen 7 5800X3D the nearest cheaper option.

Key dimensions & specs

  • L3 cache: 33MB
  • Max boost: 5.6GHz
  • Cores / threads: 20 cores
  • Rated power: 125W
  • Threads: 28
  • Socket: LGA1700
  • Memory: DDR4 or DDR5
  • Cooler in box: No
  • Integrated graphics: Yes

Pros

  • 5.6GHz maximum boost
  • 20 cores for encoding and background work
  • Integrated graphics for display output without a graphics card
  • 8 performance and 12 efficient cores

Cons

  • No cooler in the box
  • Costs more than the Ryzen 9 7900X at the time of writing
AMD Ryzen 7 5800X3D

Best AM4 Upgrade6 of 8

AMD Ryzen 7 5800X3D on Amazon (opens in a new tab)

The Ryzen 7 5800X3D is the last X3D chip for AM4.

Best for

Keeping an AM4 board.

Skip if

Pass on it if aM4 is a final-generation platform with no newer CPUs comin rules it out for your setup.

Why we like it

It lets an existing AM4 board take a cache upgrade without a new platform or DDR5. On L3 cache it ties with the Ryzen 7 7800X3D at 96MB. On boost clock it trails the group at 4.5GHz, while the Ryzen 9 9900X offers 5.6GHz.

It matches the Ryzen 7 7800X3D and the Ryzen 7 9700X on core count (8 cores). Its 105W rated power ranks second of 8 here, behind the Ryzen 7 9700X (65W) and ahead of the Ryzen 9 7900X (170W). An AM4 socket is unique to it among these picks, while the Core Ultra 7 265K uses an LGA1851 socket.

You get DDR4 memory here, which sets it apart from the Core i5-13600K and its DDR4 or DDR5 memory. On price it sat 7th of 8, between the cheaper Core Ultra 7 265K and the pricier Core i7-14700K, at the time of writing.

Key dimensions & specs

  • L3 cache: 96MB
  • Max boost: 4.5GHz
  • Cores / threads: 8 cores
  • Rated power: 105W
  • Threads: 16
  • Socket: AM4
  • Memory: DDR4
  • Cooler in box: No
  • Integrated graphics: No

Pros

  • 96MB of L3 cache from 3D V-Cache
  • 3D V-Cache on the AM4 platform
  • Drop-in upgrade for many existing AM4 boards after a BIOS update
  • Rated power of 105W, ahead of the Ryzen 7 7800X3D

Cons

  • AM4 is a final-generation platform with no newer CPUs coming
  • No cooler in the box
  • No integrated graphics, so a graphics card is required
AMD Ryzen 9 7900X

Solid Alternative7 of 8

AMD Ryzen 9 7900X on Amazon (opens in a new tab)

The Ryzen 9 7900X offers twelve Zen 4 cores at a lower price than the 9900X.

Best for

Buyers who want 64mb of l3 cache.

Skip if

Look at the others if this bothers you: 170W rating calls for a large air cooler or a 280mm-plus AIO.

Why we like it

It suits a workstation budget that still wants AM5. On L3 cache it ties with the Ryzen 9 9900X at 64MB. On boost clock it ties with the Ryzen 9 9900X and the Core i7-14700K at 5.6GHz.

It matches the Ryzen 9 9900X on core count (12 cores). Its 170W rated power is the highest in this group; the Ryzen 7 9700X leads at 65W. It also comes with the Zen 4 architecture, a 5nm process and PCIe 5.0 support on AM5.

It needs an AM5 board (A620, B650, B850, X670 or X870 series) and DDR5 memory; check the board's CPU support list for the minimum BIOS version. Budget for a dual-tower air cooler or a 240mm-plus AIO, since none is included. It was the cheapest of the group when we checked; the Ryzen 9 9900X was the next step up.

Key dimensions & specs

  • L3 cache: 64MB
  • Max boost: 5.6GHz
  • Cores / threads: 12 cores
  • Rated power: 170W
  • Threads: 24
  • Socket: AM5
  • Memory: DDR5
  • Cooler in box: No
  • Integrated graphics: Yes

Pros

  • 64MB of L3 cache
  • 5.6GHz maximum boost
  • 12 cores for encoding and background work
  • Integrated graphics for display output without a graphics card

Cons

  • 170W rating calls for a large air cooler or a 280mm-plus AIO
  • No cooler in the box
  • Rated power trails the Ryzen 7 9700X (65W)
Intel Core i5-13600K

Worth Considering8 of 8

Intel Core i5-13600K on Amazon (opens in a new tab)

The Core i5-13600K is the previous-generation fourteen-core LGA1700 chip.

Best for

Buyers who want 14 cores for encoding and background work.

Skip if

Worth skipping when no cooler in the bo is a problem.

Why we like it

It fits the same boards as the 14600K. On L3 cache it trails the group at 24MB, while the Ryzen 7 7800X3D offers 96MB. On boost clock it sits mid-pack at 5.1GHz: the Ryzen 9 9900X offers 5.6GHz, and the Ryzen 7 5800X3D comes in at 4.5GHz.

Its 14 cores core count ranks third of 8 here, behind the Core Ultra 7 265K (20 cores) and ahead of the Ryzen 7 5800X3D (8 cores). It matches the Core Ultra 7 265K and the Core i7-14700K on rated power (125W). It shares an LGA1700 socket with the Core i7-14700K; the Ryzen 9 7900X goes with an AM5 socket.

It shares DDR4 or DDR5 memory with the Core i7-14700K; the Ryzen 7 9700X goes with DDR5 memory. You also get 6 performance and 8 efficient cores and an unlocked multiplier.

Key dimensions & specs

  • L3 cache: 24MB
  • Max boost: 5.1GHz
  • Cores / threads: 14 cores
  • Rated power: 125W
  • Threads: 20
  • Socket: LGA1700
  • Memory: DDR4 or DDR5
  • Cooler in box: No
  • Integrated graphics: Yes

Pros

  • 14 cores for encoding and background work
  • Integrated graphics for display output without a graphics card
  • 6 performance and 8 efficient cores
  • Unlocked multiplier

Cons

  • No cooler in the box
  • L3 cache trails the Ryzen 7 7800X3D (96MB)
  • Costs more than the Ryzen 9 7900X at the time of writing

How We Chose

Each pick was assessed across 4 criteria weighted for real-world use.

Game-relevant specs
We compared L3 cache, boost clocks and core counts from AMD's and Intel's product pages.
Upgrade path
We considered how long each socket is likely to receive new CPUs.
Power and cooling
We recorded each chip's rated power and what cooler class it needs.
Platform cost
We noted socket, memory type and whether a cooler is included, since they change the real price.

What to Look for in a CPUs Under $400

Key buying criteria so you get the right fit the first time.

  1. Cache helps games more than clocks

    AMD's X3D chips add a large stacked L3 cache that keeps more game data close to the cores. In CPU-limited games that often helps more than a higher boost clock.

    The gain shrinks when the graphics card is the limit.

  2. Cores matter for streaming and creation

    Six and eight cores cover gaming. Streaming with CPU encoding, video editing and compiling benefit from twelve or sixteen.

    If you encode on the graphics card instead, core count matters less.

  3. Budget for the cooler

    Most unlocked chips ship without a cooler. A 65W part runs well on a basic single tower, while 120W to 170W parts need a dual tower or an AIO to hold their boost clocks.

    Add the cooler to the CPU price when comparing.

  4. Check BIOS support before buying

    Newer CPUs on older boards may need a BIOS update before the system will start. Check the board's CPU support list for the version you need and whether the board can flash without a CPU installed.

  5. Integrated graphics are a useful backup

    Chips with integrated graphics can drive a display without a graphics card, which helps when troubleshooting or between upgrades. Intel's F and KF models and most AM4 Ryzen chips have none.

  6. The socket decides your upgrade path

    The socket fixes which motherboards and future CPUs you can use. AM5 has had several CPU generations; AM4 has no newer chips coming.

    If you plan to upgrade later, a current platform is worth a small premium.

How to Choose a CPUs Under $400

By priority

PriorityConsiderWhy
Gaming-first buildsRyzen 7 7800X3D96MB of L3 on eight cores
Quiet, cool buildsRyzen 7 9700XEight Zen 5 cores at 65W
Rendering and compilingRyzen 9 9900XTwelve Zen 5 cores
Intel creator buildsCore Ultra 7 265KTwenty cores on LGA1851
Keeping an AM4 boardRyzen 7 5800X3D96MB of L3 on AM4

Scroll sideways to see every column.

Key specs side by side

Figures as each maker states them.

ProcessorL3 cacheMax boostCores / threadsRated power
Ryzen 7 7800X3D96MB5GHz8 cores120W
Ryzen 7 9700X32MB5.5GHz8 cores65W
Ryzen 9 9900X64MB5.6GHz12 cores120W
Core Ultra 7 265K30MB5.5GHz20 cores125W
Core i7-14700K33MB5.6GHz20 cores125W
Ryzen 7 5800X3D96MB4.5GHz8 cores105W
Ryzen 9 7900X64MB5.6GHz12 cores170W
Core i5-13600K24MB5.1GHz14 cores125W

Scroll sideways to see every column.

Frequently Asked Questions

Is AM4 still worth buying into?

For an upgrade to an existing AM4 system, yes. For a new build, AM5 or LGA1851 gives a longer upgrade path.

What memory should I pair with it?

AM5 and LGA1851 use DDR5; AM4 uses DDR4. For AM5, a 32GB DDR5-6000 kit is a common pairing; check the board's memory support list.

What does the rated power figure mean?

It is AMD's default TDP or Intel's base power. Chips can draw more under boost, so size the cooler for sustained loads, not the label alone.

Should I choose Intel or AMD for gaming?

At the high end, AMD's X3D chips lead in many CPU-limited games. Intel's Core Ultra chips offer more cores for work at similar prices. Choose by workload and platform cost.

Do I need to buy a separate cooler?

Usually yes. Only some chips, such as the Ryzen 5 7600 and 5600X, include a basic cooler; unlocked high-end models do not.

Will a new CPU work in my current motherboard?

Only if the socket matches and the board's BIOS supports it. Check the maker's CPU support list for the minimum BIOS version.

Bottom Line

For gaming, the Ryzen 7 7800X3D is the pick under $400. Choose the Ryzen 9 9900X or Core Ultra 7 265K for heavy work, the 9700X for low heat, and the 5800X3D to extend an AM4 build.