Best CPU for RTX 4080, should you get a new CPU?

Nvidia has unleashed its RTX 4080 onto the world, the GPU, being the little brother of the RTX 4090, isn’t quite as powerful, but it still packs a punch. So what would be the best CPU for the RTX 4080? 

Now Read: Where to buy an RTX 4080

Finding a CPU to pair with the RTX 4080 isn’t particularly difficult, as both the CPU giants, AMD and Intel, only released their latest generation CPUs in October 2022. And what a line-up we have to choose from. From the Powerful 13900K to the wildcard 5800X3D, these are the best CPUs we can recommend for the RTX 4080.

Best CPU for RTX 4080: Top picks

Here are our top picks for the best CPU to pair with the RTX 4080.

01

Best Intel CPU for the RTX 4080

Intel Core i9-13900K

Intel Core i9-13900K

02

Best Ryzen CPU for the RTX 4080

AMD Ryzen 9 7900X

AMD Ryzen 9 7900X

03

Wildcard: Ace in the hole

AMD Ryzen 7 5800X3D

AMD Ryzen 7 5800X3D

RTX 4080 specs

First off, let’s jump into the specs of the RTX 4080 to see what exactly makes it a powerful GPU. 

The basic specifications of the RTX 4080 are as follows: 

As you can see, we’re not quite reaching 4090 levels of performance, but it’s certainly the second-fastest GPU in the world currently. 

What makes a powerful CPU? 

Now we need to find a CPU to pair with our RTX 4080 and figure out the best CPU for the RTX 4080. But what makes a powerful CPU? Most of the factors we will be discussing here are just the tip of the iceberg and require a much more comprehensive explanation to gain a full understanding.

But for our purposes, they will do just fine. 

Core and thread count 

CPU cores and threads are possibly the best determining factor in whether or not a CPU is considered powerful. Of course, power relies on multiple factors such as generation, IPC, clock speed, and so on. We’ll get to those in a minute.

A CPU with more cores and threads will be better at multitasking natively, meaning that your CPU can handle multiple things at once more and more efficiently the more cores and threads you have. This kind of setup is ideal for streamers and content creators, but if you’re just a gamer you might want to consider leaning into our next factor more heavily, core speed.

Core speed

Core speed is the measurement of how fast a CPU core can complete the CPU instruction cycle. The CPU instruction cycle consists of three main actions, these are fetch, decode, and execute. As soon as this cycle is completed, that’s one instruction executed. and a CPU has billions of instructions to process every second.

The faster the CPU can execute instructions, the faster it will process information. Clock speed is measured in a frequency, which is GHz. That is (X) amount of billions of cycles per second. So, if a CPU’s clock speed is 5 GHz, that is 5,000,000,000 cycles per second. The higher the number, the faster the CPU core.

Differences between AMD and Intel CPUs

AMD and Intel are both different, meaning you need different technologies to make them compatible with the rest of your PC.

In case you weren’t aware, AMD and Intel belong to different sockets, meaning you need different motherboards to ensure compatibility. The new generation of Intel CPUs belongs to the same LGA 1700 socket as the 12th generation. So you won’t need to upgrade your motherboard there.

With AMD however, it’s a different story. AMD has moved from socket AM4 to socket AM5 or LGA 1718, meaning the older motherboards are no longer compatible. This is the same with DDR4 memory, AM5 motherboards only accept DDR5 memory.

This means the upgrade to AM5 could be costly, just another thing to consider.

Chipsets

Each processor will have a set of chipsets that it’s compatible with. These chipsets are important when choosing your motherboard, as they determine whether or not some features will be obtainable.

The more advanced the chipset, the more features will be available to you (More PCIe lanes, more USB4 ports, SATA ports, etc.). As with the socket types. The 700 series motherboards from Intel and the AM5 motherboards from AMD, both feature PCIe Gen 5 on both the M.2 SSD slots and GPU PCIe slots. That is if you go for a high-end chipset within the set, like a Z790, or X670. check your hardware specs to see what chipsets are compatible, and what each one will support on your motherboard.

For example:

RTX 4080 CPU bottleneck

What you don’t want to do, Is bottleneck your 4080 in any way. A bottleneck occurs when one component in a system is not operating to the standard of every other component in the system, this results in a slowdown.

What this looks like in terms of a CPU bottleneck, is the CPU is not powerful enough to keep feeding the GPU with information, meaning the GPU is limited by the amount of data it’s being sent to process. Essentially, it’s like tying a plastic bag around your head and running a marathon, you’ll do way worse than if you didn’t have a bag over your head, agreed?

So what does a 4080 CPU bottleneck look like? It looks like a CPU from Intel under the Core i5-12600K and under a Ryzen 5 5600X from AMD. We’d highly recommend you stick to CPUs over that limit. We know there’s not a huge amount out there over that limit right now, but anything below those outlined CPUs would just be throwing money away in terms of bottlenecking performance.

The best CPU for RTX 4080

With those fundamentals out of the way, what’s the best CPU to pair with the RTX 4080? We’ll go in order from most fitting to less fitting. As we are aware of the fact a lot of these new CPUs are pretty pricey.

You’re going to want a beefy CPU to be able to keep up with the demand of owning a 4080. This GPU is incredibly hungry and will chew through any load even the most modern CPU can feed to it.

You’re definitely best off not scrimping on a CPU, as it’s highly likely you’ll run into a CPU bottleneck, even when going for a CPU lower than the flagship on the latest generation.

Intel Core i9-13900K

Intel Core i9-13900K

P-cores 3 GHz / E-cores 2.2 GHz

P-cores 5.8 GHz / E-cores 4.3 GHz

The i9-13900K is a very powerful CPU capable of destroying the competition, Its 24-core and 32-threads annihilate in both single and multi-core workloads. fixing the 13900K at the top of multi-threaded performance for the first time in a long time.

The 13900K has a TDP of 125 W base and 253 W boost, that’s a huge leap in TDP over the last generation’s Alder Lake CPUs. But it’s also a massive jump in performance.

The 13th-generation Raptor Lake CPUs see improved single-core performance of up to 15% and multi-core performance of up to 41%. The best part is you don’t even have to upgrade your motherboard to access all of this performance, but upgrading has its benefits.

The L2 CPU cache is doubled this time, giving the CPU access to larger, faster storage. This enabled the CPU to keep processing instructions quickly without developing a backlog that results in slowdowns. The 13900K is seriously fast, with a boots core speed of up to 5.8 GHz, the fastest core speed on the market at the time of writing.

All of this performance does have a downside, however, the 13900K runs very hotly under immense stress. We don’t expect you’d ever reach the levels of usage and stress that we did in our test, but we managed to get the 13900K to throttle up to 13%. using a 360mm AIO.

This CPU is a beast, that will be bested by none. The 13900k will keep the 4080 fed relentlessly with its immense amount of cores and the speeds at which they operate. The RTX 4080 would be lucky to have the i9-13900K.

Ryzen 9 7900X

AMD Ryzen 9 7900X

Pros

• 
  
  
  Incredible performance
• 
  
  
  High performance pew Watt
• 
  
  
  Interesting IHS
• 
  
  
  Cooler than other 7000 series CPUs on average

Cons

• 
  
  
  A little pricey
• 
  
  
  Hard to keep cool

The 7900X is part of the brand-new Zen 4 architecture, AMD has truly brought the performance to another level on the new AM5 platform. The 7000 series is brought into the present with the AM5 socket providing support for both DDR5 and PCIe Gen 5.

The 8-core, 16-thread Ryzen 7900X is capable of massive multi-core performance as well as single-core performance thanks to its massive 5.6 GHz boost clock speed. AMD has massively increased performance this time, and it hoping it’s going to be enough to stave off Intel.

Cache has been doubled this time around, now 1MB per core as opposed to 512KB, this means more instruction buffering and less likely the CPU will be caught in a backlog of instructions, causing slowdowns.

The 7900X’s TDP is 170 W at the base core speed and 230 W at the boost speed. This also unfortunately makes the CPU run much hotter than anyone wants, just like the 13900K. It seems CPU cooler technology just can’t keep up with the amount of power packed into the new generation of CPUs.

This CPU is a gaming giant, as well as packing enough cores and threads to handle the multithreaded workloads of content creation and streaming, the perfect high-end AMD CPU for the RTX 4080.

Ryzen 7 5800X3D

AMD Ryzen 7 5800X3D

Pros

• 
  
  
  Inexpensive
• 
  
  
  Incredible performance
• 
  
  
  3D V-cache

Cons

• 
  
  
  No cooler
• 
  
  
  No native overclocking support

If you’re on last-gen AMD, and a lot of research suggests that you are, then you might want to consider the Ryzen 7 5800X3D. Since it annihilated 12th-generation flagships in outright gaming performance.

The Ryzen 7 5800X3D is a marvel in CPU engineering, the 5800X3D has claimed the top ‘best gaming CPU’ from Intel and their core i9 12900K of the last generation, but there are a couple of reasons it’s not top of our list today.

The 5800X3D is an excellent choice for gaming, donning eight multithreaded CPU cores and a massive 96MB of brand-new AMD 3D V-cache, which is an unhead-of amount of cache for a CPU, not even the next-gen flagships have as much as this CPU.

3D V-Cache is where this CPU differed from literally every CPU in the world right now, (before the release of Zen 43D) as it’s the only one to make use of it.

The 3D cache is not stacked laterally like a normal 2D cache but vertically (thanks to new 3D printing technology) – hence the term 3D cache. This drastically increases the number of chiplets you can cram into an area of any given size. The vertical stacking allows AMD to achieve the massive 96MB L3 cache with a total access speed of 2TB/s in its 5800X3D CPUs.

The 5800X3D has lower core speeds of 3.4GHz base and 4.5GHz max, these speeds are even lower than its brothers the 5800X, The reason for this is the 3D V-cache instability at higher clock speeds. This is also why overclocking is disabled on this CPU as standard.

Summary

This new caching technology gives the CPU major advantages in some gaming workloads, but not all. And with the lower core speeds and lack of overclocking support on our means, the 5800X3D is regularly outperformed by cheaper and worse CPUs in scenarios where the cache is not utilized, even in gaming.

The 5800X3D is still a bit of a wildcard for pure gamers out there. And one that should be considered for the RTX 4080, especially if you have no money left after buying said 4080. As the 5800X3D can be had for one heck of a deal these days.

For these main reasons, is why the 5800X3D is not higher on our list. You can read the full product review on the Ryzen 7 5800X3D right here.

i9-12900K

Intel Core i9-12900K

Boost clock speed (single core)

Pros

• 
  
  
  Powerful single core performance
• 
  
  
  Powerful multi-core performance
• 
  
  
  Overclockable

The 12900K is the successor to the 11th gen Intel i9-11900K, utilizing the new ‘Alder Lake’ architecture as opposed to the ‘Rocket Lake’ of the older CPU. Unlike the release of Intel’s 11900K, the 12900K was a massive hit among reviewers.

The 12900K comes with a 125W TDP which is higher than the AMD 5950X, which is only 105W, meaning it does get a little hot on the CPU die. Not as hot as the 13900K does, thankfully. The 12900K is only compatible with the LGA1700 socket, meaning a complete upgrade from LGA 1200 will be necessary if you plan on purchasing this CPU. The good news is, however, this CPU will work with both 600 and 700 series Intel motherboards.

The i9-12900k comes to shelves boasting a core count of 16 and 24 threads, making it a great all-rounder for both multitasking and gaming. Intel has put its efforts into architectural improvements with the new Alder Lake lineup, improving in almost every area.

With all these improvements, we finally saw Intel regain the top spot as far as gaming is concerned. More impressive, however, is the fact that in workstation and multitasking scenarios. The Core i9-12900k is almost on par with the 5900X in multi-core performance. Pair that with the better single-core performance and the crazy overclocking potential that Intel holds, and you all of a sudden have one heck of a CPU for the RTX 4080.

Best CPU for RTX 4080 FAQs

Here we have some of the most frequently asked questions when searching the web for the best CPU for the RTX 4080.

What is the best CPU for the RTX 4080?

Arguably, the best CPU on the market right now for the RTX 4080 is the Core i9-13900K. Its high core counts paired with its 5.8GHz boost clock speed makes this the ideal candidate to support the beastly RTX 4080.

Do I need to upgrade my CPU for the RTX 4080?

We wouldn’t recommend trying to run with an RTX 4080 if you have a CPU below the i5-12600K or the Ryzen 5 5600X. If you have a CPU lower than that, then you should consider upgrading.

---

Final word

Choosing the right CPU for the 4080 can be tricky, as you want to match its power in the most cost-effective way possible. We assure you that the CPUs on this list is nothing but the best. You won’t miss a beat choosing any one of the CPUs we have on offer today. Will it be the 13900K titan? or the 7900X from AMD? The efficiency champion.

Both Intel and AMD offer up some high-performance flagships and should be seriously considered for the supporting role in your RTX 4080.

You’d better make sure you have the correct prerequisite hardware, as AMD and Intel require different motherboards to utilize.

We hope you enjoyed this Best CPU for RTX 4080 article.