What is a CPU cache? In one sentence, it is a small pool of extremely fast memory built into your processor that keeps the data the CPU needs next within arm’s reach. Because it sits right next to the processing cores, the CPU can read it far faster than it can read your system RAM. The bigger and smarter that cache is, the less time your processor spends waiting, and the smoother your games feel.
Cache used to be a footnote on spec sheets. That changed when AMD released its X3D processors, which stack extra cache on top of (or underneath) the cores and jumped to the top of gaming benchmarks. In this guide we explain how CPU cache works, what L1, L2 and L3 mean, why an X3D CPU is so good for gaming and how much cache you should look for in your next PC.
What is a CPU cache, in plain English?
Think of your PC as a workshop. Your storage drive is the warehouse down the road: huge, but slow to get to. Your RAM is the storeroom out the back: much quicker, but still a walk away. The CPU cache is the bench right in front of the worker, with the tools for the current job laid out within reach.
Every time a processor needs a piece of data, it checks the cache first. If the data is there, that is called a cache hit, and the core keeps working almost instantly. If it is not there, that is a cache miss, and the core has to fetch the data from RAM. A trip to RAM can take hundreds of clock cycles, which is a long time for a processor that completes billions of cycles every second.
So when people ask what is a CPU cache for, the real answer is this: it hides the slowness of everything else. A processor with a large, well-designed cache spends more of its time doing useful work and less time waiting for memory.
Why the CPU cache is so small
Cache is made from SRAM, a type of memory that is very fast but takes up a lot of space on the chip and costs far more per gigabyte than the DRAM in your memory sticks. That is why even high-end processors have cache measured in megabytes while system RAM is measured in gigabytes. Designers have to balance size, speed, power and cost very carefully.
L1, L2 and L3: the three levels of CPU cache
Modern processors split their cache into levels. Each level is larger but slower than the one before it, and the processor checks them in order.
| Cache level | Typical size | Speed | Shared or private |
|---|---|---|---|
| L1 | Tens of KB per core | A few clock cycles | Private to each core |
| L2 | Around 1MB to 3MB per core | Roughly 3 to 4 times slower than L1 | Usually private to each core |
| L3 | Tens of MB, up to 128MB on some X3D chips | Slower than L2, still far faster than RAM | Shared by a group of cores |
| System RAM | 16GB to 64GB in a gaming PC | Hundreds of cycles away | Shared by the whole system |
L1 cache
L1 is the smallest and fastest level. Each core has its own L1, usually split into an instruction cache (the steps the core is about to run) and a data cache (the values it is working on). It is tiny, but it is accessed constantly, so it has to respond in just a few cycles.
L2 cache
L2 is a middle layer that catches what does not fit in L1. On AMD’s Zen 5 processors each core has 1MB of L2. Intel’s recent Core Ultra chips give their performance cores even more. L2 smooths out the work of each individual core.
L3 cache
L3 is the big shared pool, and it is the level that matters most for gaming. When marketing material talks about how much cache a chip has, it is usually talking about L3. A standard eight-core Ryzen 9000 chip has 32MB of L3, while the Ryzen 7 9800X3D has 96MB thanks to AMD’s stacked cache.
How a CPU cache speeds up your games
Games are a worst case for memory. A modern title is constantly juggling the positions of characters, physics objects, AI decisions, audio and the long list of draw calls sent to the graphics card. Much of that data is accessed in unpredictable patterns, which means the processor cannot easily guess what it needs next.
Every time the CPU stalls waiting for data, the graphics card waits too, because it cannot draw a frame until the processor has prepared it. A larger cache means more of the game’s working data stays close to the cores, so there are fewer stalls. The result is not just a higher average frame rate. It is better 1% lows, which is what you actually feel as smoothness when a scene gets busy.
This is why two processors with similar clock speeds and core counts can perform very differently in games. The one with more cache, and smarter cache, often wins comfortably.
What is an X3D CPU?
An X3D CPU is an AMD Ryzen processor with 3D V-Cache, an extra slice of SRAM bonded directly to the processor die. Rather than spreading more cache sideways across the chip, AMD stacks it vertically, which adds a large amount of L3 without making the chip physically bigger. You can read AMD’s own overview of 3D V-Cache technology for the engineering details.
The first desktop X3D chip arrived in 2022, and the idea quickly proved itself in games. The Ryzen 7 7800X3D became a favourite for gaming builds, and the Zen 5 based Ryzen 7 9800X3D took the crown in late 2024. AMD followed with the 16-core Ryzen 9 9950X3D in 2025 and the faster-clocked Ryzen 7 9850X3D in January 2026.
What changed with second-generation 3D V-Cache
Early X3D chips placed the extra cache on top of the cores, which made heat harder to remove and forced lower clock speeds. With the Ryzen 9000 X3D range, AMD moved the cache underneath the cores. The cores now sit directly against the heat spreader, so the chip runs cooler, clocks higher and can be overclocked. In practice, a modern X3D chip gives up very little in everyday tasks while keeping its big lead in games.
Popular X3D CPU options in 2026
- Ryzen 7 7800X3D: eight cores, 96MB of L3 cache and still an excellent gaming chip on the AM5 platform.
- Ryzen 7 9800X3D: eight Zen 5 cores, 96MB of L3 and a 5.2GHz boost. The most popular gaming processor we build with.
- Ryzen 7 9850X3D: the same layout as the 9800X3D with a higher 5.6GHz boost clock, for a small extra gain.
- Ryzen 9 9950X3D: sixteen cores and 128MB of L3, ideal if you game and also render, stream or compile code.
Our Ryzen 7 9800X3D guide goes deeper on the chip most gamers end up choosing.
How much CPU cache do you need for gaming?
There is no single magic number, but there are useful rules of thumb based on what we see when we benchmark systems on the bench.
- Office work, study and web browsing: any modern processor has more than enough cache. Spend your money on an SSD and enough RAM instead.
- 1080p and 1440p gaming on a budget: a standard six or eight-core chip with 32MB of L3 performs well, especially when paired with an RTX 5060 or RTX 5070 class graphics card.
- High refresh rate gaming: if you play competitive shooters at 144Hz to 360Hz, an X3D CPU makes a noticeable difference because the processor is often the bottleneck at those frame rates.
- 4K gaming: the graphics card does most of the heavy lifting, so cache matters less for average FPS. It still helps the 1% lows, which is why we pair X3D chips with high-end cards.
- Gaming plus content creation: look at a 16-core X3D CPU such as the 9950X3D, which combines a big cache with plenty of cores for rendering.
Cache is one part of a balanced system. Memory speed and capacity also matter, which is why we cover them in our DDR5 RAM guide.
CPU cache vs RAM vs VRAM: what is the difference?
These three types of memory get mixed up all the time, so here is a quick comparison.
- CPU cache lives inside the processor. It is measured in megabytes and is the fastest memory in your PC.
- RAM is the system memory on your motherboard. It holds the operating system, open programs and game data. It is measured in gigabytes and is much slower than cache.
- VRAM is the memory on your graphics card. It holds textures and frame data for the GPU. More VRAM matters at higher resolutions, which we explain in our guide to what a GPU does.
Adding more RAM will not give you more cache, and a graphics card with lots of VRAM will not fix a processor that is short on cache. Each one solves a different bottleneck.
Does CPU cache affect anything other than games?
Yes, although the effect varies. Large datasets in scientific computing, some database workloads and code compilation can all benefit from a bigger cache. Video rendering and 3D rendering, on the other hand, tend to scale more with core count and clock speed than with cache.
That is why AMD’s 16-core X3D chip makes sense for creators who also game, while a pure gaming build is usually best served by the eight-core models. If your PC is mainly for professional work, have a look at our workstations, where we size processors for the software you use.
How to check how much cache your CPU has
If you want to know what your current processor offers, Windows can tell you in seconds.
- Press Ctrl, Shift and Esc together to open Task Manager.
- Select the Performance tab, then click CPU.
- Look under the graph for L1 cache, L2 cache and L3 cache values.
For more detail, free tools such as HWiNFO list every cache level per core and show live clock speeds and temperatures. Our guide on how to check CPU temperature walks through those tools step by step.
Common myths about CPU cache
Myth: more cores always beat more cache
For games, the opposite is often true. Most games lean heavily on a handful of threads, so an eight-core X3D chip usually beats a 12 or 16-core chip without the stacked cache. Extra cores shine in rendering and multitasking, not in frame rates.
Myth: you can upgrade CPU cache later
You cannot add cache to a processor. It is part of the silicon. The only way to get more cache is to choose a different processor, which is why it pays to get the decision right when you buy.
Myth: cache only helps at 1080p
The biggest gains appear when the processor is the bottleneck, which is most common at 1080p and high refresh rates. At 1440p and 4K the gains in average FPS shrink, but smoother 1% lows still make a difference in busy scenes and simulation-heavy games.
Which Elite Gaming PCs builds use an X3D CPU?
Because the gaming benefit is so clear, a big share of our gaming range is built around X3D processors. Here are some of the systems we build most often.
- The 9800X3D RTX 5080 gaming PC pairs AMD’s most popular gaming chip with a 4K-capable graphics card.
- The 7800X3D RTX 5070 gaming PC is a smart 1440p choice that still benefits from 96MB of L3 cache.
- The 9950X3D RTX 5090 gaming PC is our flagship for people who game at 4K and create content on the same machine.
You can see the full list in our AMD Ryzen gaming PCs range, which shows the processor, graphics card and memory for every build.
Cache, clock speed and cores: how they work together
A processor’s performance comes from three things working as a team. Clock speed sets how many cycles each core completes per second. Core count sets how many tasks can run side by side. Cache decides how often each of those cores has the data it needs ready to go.
Improve one and ignore the others and you will hit a wall. A very fast core that keeps waiting on memory wastes most of its speed. A chip with many cores helps when software can split work across all of them, but games rarely use more than six to eight cores heavily. Extra cache makes every one of those cores more efficient, which is why it has such a strong effect on frame rates.
Architecture matters too. Each new generation brings better branch prediction, wider execution units and smarter prefetching, which is the hardware guessing what data will be needed next and loading it early. A newer processor with the same headline numbers as an older one is usually quicker for exactly these reasons.
A quick checklist for choosing your next processor
When customers ask us to recommend a processor, we run through the same short list of questions. They will help you narrow down the options in a few minutes.
- What will you play? Competitive shooters and strategy or simulation games lean hardest on the processor. Story-driven single player games at high resolution lean on the graphics card.
- What screen will you use? A high refresh rate monitor raises the demand on the processor, because it has to prepare more frames every second.
- Will you stream, edit or render? If so, consider more cores so background work does not interrupt your game.
- How long will you keep the PC? A stronger processor today leaves room for a graphics card upgrade in two or three years without needing a new platform.
- What is your total budget? For most gaming builds the graphics card should still take the largest share, with the processor a close second.
Answer those and the right chip usually becomes obvious. If you are still torn between two options, send us your shortlist and the games you play and we will give you an honest recommendation.
Keeping your processor fast for years
A well-chosen chip should stay quick for a long time, provided it is looked after. Keep the case clean so dust does not choke the fans and heatsink. Keep your BIOS, chipset drivers and Windows up to date, because platform updates often improve memory compatibility and boost behaviour. And check temperatures now and then, especially in summer, so you notice if a cooler or fan starts to fail.
Every Elite Gaming PCs system is stress-tested before it leaves our bench in Gregory Hills, and our 12-month warranty covers you if something goes wrong. If you ever notice performance dropping, get in touch and we will help you track down the cause.
The bottom line on CPU cache
So, what is a CPU cache worth to you? If you mostly browse, study or work in office apps, cache is not something you need to think about. If you play games, especially at high refresh rates, it is one of the most important specifications on the box, and an X3D CPU is the easiest way to get more of it.
Pair a cache-heavy processor with a graphics card that suits your monitor, give it enough memory and keep it cool, and you will have a PC that feels fast in every game. If you would like help choosing, our team is always happy to answer questions by email, or you can browse more explainers on our gaming PC blog.
CPU cache FAQ
Is more CPU cache always better?
For gaming, more L3 cache is usually better, but the gains depend on the game and resolution. For everyday tasks, extra cache makes little visible difference.
What is a good amount of L3 cache for gaming?
32MB is solid for mainstream builds. 96MB, found on X3D chips like the 9800X3D, is the current benchmark for high refresh rate gaming.
Is an X3D CPU worth it for 4K gaming?
It helps less than at 1080p because the graphics card is usually the limit, but it still improves 1% lows and future-proofs the system for faster GPUs.
Does CPU cache affect temperatures?
Stacked cache can make a processor slightly harder to cool. AMD’s second-generation design reduces this, and a good tower cooler or AIO keeps any X3D chip comfortably within safe limits.
