Should I Buy A Used CPU? (Full buyer’s guide)

I’ve bought used CPUs since I started building PC’s back in the 90’s (yes, I’m old!). And not a single used CPU has failed on me. 

My last CPU, before my current one, was the trusty ‘Intel i5 2500K’. This 4 core processor was my trusted companion through dank dungeons, towering tombs, and rain-soaked race tracks. It stayed by my side, loyal to the end, for 5 years. 

New, this CPU would have cost me £250. My ‘i5’ CPU was won at auction on eBay for just £40. 

I then stepped up my game and purchased an ‘i5 6400’, which is another Intel CPU. Again, this was bought off eBay at auction and it cost me £37.50. 

And it’s still purring along perfectly today. 

But, surely there are issues and problems that raise their ugly chip melting head when you buy a used CPU? 

Well, as somebody with experience in buying used CPUs for many years, I wanted to answer this question, along with loads of other used CPU questions, for you in this article. 

Should I buy a used CPU? Yes, you should buy a used CPU. Used CPUs offer far more processing power per dollar spent than new CPUs. Plus, you’re saving perfectly good CPUs from ending up in landfill sites. In this article we’ll look at:

  • I’ll answer the question “Should I buy a used CPU” in more depth
  • You’ll get a list of where you can buy used CPUs 
  • Why buying a used ex-business PC might be the best idea
  • Look at the difference between a used CPU and a refurbished CPU
  • Take a look at some of the problems you could potentially encounter when buying a used CPU
  • Tips/checklist for buying a used CPU
  • Explore why buying a used CPU may not be the right move for you
  • A conclusion and a look at what you can do next

Ok, now you know what I’ll cover in this article, let’s crack on and take a closer look at each section…

But first, a quick note… 

Sorry that everything discussed in this article is talked about in pounds. I wanted to be as authentic as possible by using my own experience of buying used PC parts here in the UK. UK prices can be converted to US dollars. 

Why should you consider buying a used CPU? 

Buying a used CPU… Saves you money 

The most obvious reason why you should buy a used CPU is because you could potentially save a lot of money. 

New CPUs are released each year by Intel and AMD. But what they neglect to tell you is this: real-world performance gains, in other words, performance improvement with games, usually increases by only 5-10%. If that. 

A CPU such as the ‘i5-10600k’ sells for £250. The 2-year-old ‘i5-8600k’ sells often on eBay for £125, or even less. Which is half the price. Yet, when comparing gaming performance, there is less than a 1% difference between these two CPUs.

Take a look here on UserBenchmark (amazing website) to see what I mean. 

That £125 saved, can be used to buy a better CPU, or more ram. 

To me, there is a clear winner: The used CPU. 

Buying a used CPU… Helps save the environment 

It’s a sad fact of modern life that we live in a disposable culture. Technology that has many years of useful life left is disposed of without hesitation by consumers. 

Our society is obsessed with yearly incremental improvements in our technology that add no real tangible value to our lives. CPU, GPUs, motherboards, and cases, all end up in landfill sites to make way for the next “Big thing”. 

And the cost of this obsession is the slow, and unnoticed death, of our planet’s life support system as it is suffocated by silicon assassins.

CPUs are a great example of this disposable culture in action. Every year, Intel releases a new batch of ‘Core i5’ and ‘i7’ CPUs. And every year, Intel’s marketing department goes into overdrive to convince the masses of gamers that they need their new CPUs.

Yet, these new generation buys often only offer as little as a 5% increase in computation power over the previous generation. And yet, we are expected to pay a premium for their ownership.

By buying a used CPU, you’re not only getting 95% of the processing power of the latest CPUs at massive discount. You’re saving another piece of perfectly good silicon from rotting in landfill for the next 10,000 years.  

Buying a used CPU… Gets you more processing power for your money 

Not only do you save money by buying a used CPU, but you actually get more computing power per pound, or dollar, spent. 

Let’s take a look at an example: 

A new CPU from Intel, we’ll call it ‘CPU-N’, Costs $100 and runs your game at 100fps. 

That means you’re paying $1 for every frame. Not bad.  

However, our used CPU, we’ll call it ‘CPU-U’, costs $50 and runs your game at 90 fps. 

That means you’re paying $0.56 for every frame. Even better! 

That means that ‘CPU-U’ is 90% the power of the ‘CPU-N’, but it is 44% cheaper per frame! 

Or in other words, you’re paying $50 extra dollars, or double the cost of the used CPU, for only a 10% gain in performance.   

The moral of this math strewn story: Buy used if you want the best bang per buck performance.

Where can I buy used CPUs? 

This is my list of the best places to buy used and refurbished CPUs. If you can think of anywhere else that I could add to this list, let me know in the comments. 



  • UK 
    • CeX – Offers a good 2 year warranty, but you do pay a little extra fee for this. 
    • Game – Sometimes sells used computer components, but not often. Usually sells them cheap.

Should you buy an used ex-office PC with a used CPU?

Buying an ex, used business PC in another option in your upgrade toolbelt.

Most businesses replace their “old” PCs every two to three years in an effort  to reduce the amount of tax they pay.

These “old” two to three year old PCs are sold, in bulk, to buyers. These buyers, who often run small companies on eBay, then refurbish these PCs and then sell them through the auction site. 

And these office PCs are usually stuffed like an egg full of great parts such as high end CPUs, RAM, and SSDs.

Because of this, eBay is crammed full of amazing used PCs that are ready to be ripped open, fitted with new CPUs, and turned into monstrous, yet cheap, gaming rigs.

You regularly find computers that are sporting CPUs that are only 2 or 3 years old for well under $300.

In fact, around 3 years ago, I bought a used office PC that had 16GB of ddr4 RAM and an ‘Intel i5 4600’. And I paid around £140 for it. This PC and it’s CPU is still going strong today as my Media Center computer.

However, I could have easily turned this into a really powerful gaming PC by just dropping a powerful CPU into it.

Yes, I’d need to replace the power unit. Business PCs come with built for purpose low power PSU. But, this is a tiny price to pay when you consider the amount of money you save buying a ready-made ex-office used PC.

If you want a top-end used CPU, think about buying a used ex-office PC. 

Take a look at this example of a used HP ex-office pc on Amazon.

Or take a look at this example on eBay

What’s the difference between a refurbished and just a plain used CPU? 

What are the differences between refurbished and used CPUs? 

Generally, used processors are CPUs that were bought by an individual person. They used the CPU, for gaming or work, then sold them when they were looking to upgrade to a better CPU. 

You’ll find a lot of these used CPUs on websites like eBay. They are usually sold as seen. They come with no warranty and the only protection you get is what PayPal offers. Which is still pretty amazing protection as if the CPU doesn’t work, you can send it back and get a refund. 

Refurbished CPUs are still used. But there is one key difference. 

Refurbished CPUs are usually sold by businesses not individuals. To be considered refurbished, first the CPU is thoroughly cleaned and checked for physical defects. Then the CPU undergoes industry standard tests by qualified technicians to ensure the CPU runs correctly. If it works correctly, the CPU is certified as working  by the technician, and the CPU is put up for sale. 

Refurbished CPUs are often sold with a limited 1-2 year warranty. 

I would say it is less risky to buy refurbished CPUs because you know a technician has checked the CPU, and because you get a warranty. 

However, you will pay a premium for this refurbishment process and the warranty.

Problems you may encounter with a used CPU and how to solve them 


It’s worth me pointing out that in all the time I’ve spent buying used CPUs, I have never encountered any of the above problems. 

However, I wanted to make you aware of the potential problem you may face , regardless of how small they may be. 

Tips/checklist for buying a used or refurbished CPU

Tip 1: Aim to buy a CPU that is 2-4 generations old 

When buying a used CPU, it’s best to aim to get one that is at least 2 generations old, and at most 4 generations old. 

You will still get very good performance from Intel CPUs from the ‘i5 4000’ series and up. 

For example, the ‘Intel i5-6400’ can be bought off eBay for often less than $75. 

Yet, the newest processor equivalent, the ‘i-5 10400’, will cost you $180 plus. Yet, it’s only around 15% faster than the 3 year old ‘6400’. 

For AMD CPUs, I’d aim for nothing older than a first generation Ryzen processor. For example, the ‘Ryzen 1600’. 

These CPUs can be bought for as little as $90. And they offer around 88% the performance of the latest ‘Ryzen 3600’. But then the newer processor costs $180. So, by buying a 2 generations old CPU, you’re getting 88% the performance, for half the price. 

Not bad. 

Tip 2: Step up your CPU one tier 

You may be concerned that by buying a used CPU you are losing some performance compared to newer CPUs. 

Well, you are. But not a lot. Usually, CPUs lose about 5%-10% of their performance every time a new generation comes out. 

However, you can mitigate this, to a certain extent, by stepping up a CPU tier. 

For example, a ‘i5-6400’ will be around 20% slower than an ‘i5-10400’. 

But, for a little extra, I’m talking $10-20, you can upgrade to the next tier, in this case an ‘i7’ processor. 

You can buy a ‘i7-6700’, and it’ll offer nearly identical performance to the much newer ‘i5-10400’. 

So, think about tiering up. 

Tip 3: Compare old CPUs to newer CPUs

The price of new and used CPUs are in constant flux. 

The laws of supply and demand mean that the price of PC components is forever in motion.

So much so that you often find new CPUs are, for short periods of time such as around Black Friday, are much cheaper than used CPUs. Or that the price has become so small, you may as well just buy a new CPU anyway. 

So, be sure to check all the prices before choosing a used CPU. 

Tip 4: Shop around 

There is a price difference between used CPUs sold by individuals, and refurbished CPUs sold by business. 

Usually, you’ll pay a premium for a refurbished part. 

But that isn’t always the case. Be sure to shop around, as you may find a refurbished CPU selling for less than a used, individually sold CPU, and it’ll still come with all the perks of being refurbished. 

Tip 5: Look for evidence that it works 

If you are buying used instead of refurbished you always take on a little more risk. Not much though as you are protected by PayPal if buying through eBay.

However, it’s still worth asking the seller to show you the CPU is working by placing it inside a PC, and demonstrating that it works through a monitor. 

Often, most sellers will place images showing this information. That’s ok. 

But, if there is no evidence to show the CPU actually working, and they can’t/won’t provide you with any, either get a deep, deep discount on the CPU or walk away. 

Tip 6: Has it been overclocked

Discover if the CPU has been overclocked. If it has, that could, but not often, limit the lifespan of the chip. 

Don’t be put off an overclocked CPU if it’s priced well. 

Tip 7: Paypal offers buyer protection: use it 

Do not pay in cash, and do not just transfer money directly from your bank account to the seller’s. 

Use Paypal as it offers very strong buyer protection. 

So, if the CPU arrives and it was a dud, you can get your money back. 

Tip 8: Warranties are great so long as you don’t pay too much extra  

But be aware than you may pay a slight premium on refurbished parts that come with a warranty. 

I buy used PC parts from all over the world, and rarely get warranties with them. But a warranty can provide some confidence in the part you are buying.

Plus, it’s good insurance: you know, if the part suddenly stops working in 11 months, you can send it back and get a replacement.  

Tip 9: Sell your old CPU to help pay for your new used one

Don’t let your old CPU rot away in the dark under your bed. And absolutely don’t throw it in the trash. 

Somebody out there can make use of your old CPU. Even if it’s just to make a basic media server. 

Give it a second chance at life and sell it on eBay. Then take the cash you’ve made from it and buy an even better CPU.

Tip 10: Wait for the new Generation of CPU to come out before buying an used one

Old CPU prices always drop right after a new generation of CPU is launched. So, don’t buy an used CPU a month before a new generation is due out. You are literally throwing money away then.

Wait a month, buy after the new generation arrives, and you’ll reap the financial rewards. 

Tip 11: Buy more cores

Games are starting to use more and more cores, so if in doubt when buying an old CPU, buy the CPU with the most cores. 

As time moves forward, and the next gen consoles get a footing on the market, more and more games will take advantage of 6, 8, or more CPU cores. 

So, if in doubt, buy the CPU with the most cores. 

Why shouldn’t you buy a second-hand CPU? 

I couldn’t honestly send you on your way without giving you a good counter-argument for why buying used could be the wrong choice for you. 

After all, whichever way you buy a CPU, it’s a lot of money to spend. Here are a few reasons why you shouldn’t buy a used CPU:

  • Used CPUs don’t come with a manufacturer’s warranty
  • You may not be able to send it back as easily if you buy from an individual seller
  • New CPUs will be more powerful for the same tier of CPUs
    • Example: An ‘Intel i5-10600’ will be more powerful than an ‘Intel i5-8600’
  • A lot of the time, you won’t know the CPUs history and if it’s been overclocked
  • Very old used CPUs may not use current technology 
    • However, it would have to be a very old CPU 


I honestly believe that buying a used or refurbished CPU is a great way to get more computing power in your rig by spending less money. 

Plus, you’re helping to save the earth. 

But the big draw in for me is the money you can save. So, check out some of the websites I mentioned above, your next processor could be listed on them right now. 

What next? 

Can I buy other used refurbished parts? Yes. GPUs, CPUs, motherboards, Blu-ray drives, you name it, I’ve bought it used and built a system out of it. I’ve never had any failure or problems. 

What about used fans/cases? Yes, you can buy used cases and fans. You can also buy used cooling solutions. 

What about the PSU? I have bought used PSUs in the past and they have worked absolutely fine. However, PSUs degrade over time. Their power output drops by about 5% every year, so, an old PSU will supply less power than a new PSU. That being said, if you buy a very powerful old PSU, it should easily have enough power to power even the most power-hungry modern components.  

Beth Morris

Beth's love of gaming started when she first played Frogger on her Tiny PC. Since then she's developed a love for FPSs, a need for speed playing Forza, and a hunger to find dragon's eggs in Spyro! When she's not gaming she's either cooking, reading, or spinning around in her car!

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