If you’re building your own PC, you’ll need to think about the operating system you’d like to use.
Windows is the most popular choice, whether you’d rather go for Windows 10 (it’ll be supported until October 2025) or Windows 11. But even if you opt for the former, you’re still looking at well over $100/£100 just for software.
However, from shopping around online you might have found sites selling what seems like a full version of Windows at a much lower price. These can be very tempting, especially if you have a strict budget for the total PC build.
Is it worth the risk, or are you better off just buying at full price? Here’s everything you need to know.
What is an OEM licence?
Many of the cheap versions or Windows 10 and 11 you’ll see online are described as the ‘OEM version’. OEM stands for Original Equipment Manufacturer and is a term applied to companies that build PCs. Those desktops and laptops usually include a copy of Windows, meaning it’s pre-installed and ready to use out of the box.
While the majority of OEM versions end up preinstalled on devices, it’s also possible to buy them as licence keys from third-party sites. This isn’t unusual when you’re building a new PC.
How is an OEM licence different to a retail version of Windows?
Most people never buy a copy of Windows itself. They buy a device that has Windows on it, and only ever have to worry about updates that are available in Settings.
But for those who want to purchase just the operating system, a retail version is the most popular. Physical versions on a disk or USB are still available from some retailers, but a digital download and licence key is much more popular. Here’s how much you could expect to pay at full price:
- Windows 11 Home – $139/£119.99
- Windows 11 Pro – $199.99/£219.99
- Windows 10 Home – $139/£119.99
- Windows 10 Pro – $199/£219.99
Microsoft
In reality, there is no difference at all between OEM or retail versions. Both are full versions of the operating system, include all the features, updates functionality you’d expect.
However, there are two key differences that it’s worth being aware of: support and flexibility.
When you buy an OEM copy, you’re essentially taking on the role of the manufacturer of your device. This means that if you have hardware compatibility problems or issues with activation, Microsoft will probably point you in the direction of the device’s manufacturer. Which, in this case, is technically you.
The second major difference is how many devices one copy can be used on. Retail versions can be installed on more than one device (just not at the same time), while the OEM version can only be used on the hardware where it was first activated.
This might not seem a major issue, but you’ll run into issues if you ever want to change the motherboard on your PC in the future. The new hardware means an OEM copy is no longer compatible, so you’ll need to buy it all over again.
Should I buy a cheap OEM key?
There’s nothing illegal about buying an OEM key, so long as it’s an official one. There are plenty of legitimate sites online that deal in this kind of software, including the following:
However, that doesn’t mean ever listing on these sites will be legitimate. Make sure you read the description carefully and check user ratings before spending any money. If you’re at all unsure, it’s best to look elsewhere.
Some very cheap offers might be for copies of Windows 10 or 11 in a foreign language. This can easily be resolved by downloading English language packs, which are free and available from Microsoft.
So, as long as you’re happy to take on the responsibility of being your own technical support, an OEM version can save a lot of money while offering an identical experience.
But you might prefer the extra peace of mind of a retail version, complete with full access to customer services at Microsoft.