Server vs. Desktop CPUs: What are the differences?

A common question amongst our readers is which processor type they should choose: Server or Desktop.

While it may seem intuitive to choose the option that provides the best bang-for-buck and build your system around the processor, it often pays to take a closer look.

“Server” and “Desktop” are not just categories of processors but make up separate platforms of which the processor is a part of.

We’ll be taking a quick detour through Computer Platforms to better explain the difference between Server and Desktop CPUs. You can also skip the detour and jump directly to the answer.

What type of Platforms are there?

There are four major platforms:

1. Mainstream / Consumer, sometimes defined as Desktop
2. Workstation or HEDT (High-End Desktop)
3. Professional Workstation
4. Server

There’s no official definition of what each of these platforms consist of, but generally, they’ll be split into broad tiers of form-factors, hardware performance, expandability & specialization, and intended use-case.

The different platforms compared

Desktop/Consumer/Mainstream

Typical Desktop PC Setup

The mainstream or consumer platforms are what you would use in a computer built for light workloads like graphic design, word-processing, browsing, and general everyday work and gaming.

Desktop platforms are also evolving to perform better in multi-threaded workloads, making them a cheaper alternative to workstation platforms. One good example is CPU rendering, where this platform is starting to gain popularity thanks to ever-increasing CPU core counts.

Workstation/HEDT

Workstation platforms are suited towards more demanding workloads which require strong multi-threaded performance and better connectivity. By providing many processing cores and access to more e.g. PCIe-Lanes, applications that are well-parallelized run great on this platform.

Workstation platforms fit into desktop form-factors, making them ideal for use on a desk at work or home, where you are actively working on the system.

Professional Workstation

The Professional workstation platform offers many features you would find in a high-end server platform  – the key difference being that it fits into a desktop form-factor.

This platform is ideal for applications like rendering, simulations, or workloads that need access to even more PCIe-Lanes, ECC Memory, larger Memory Capacities, or CPU Security features than the Workstation/HEDT Platform can provide.

Server

The server platform is primarily made for reliability, flexibility, and scalability. They are deployed mainly as rack-mounted units in data centers, allowing a large amount of computing power to be packed into a small amount of space.

Server platforms are configured for multiple uses ranging from high-capacity storage to performance-intensive applications with many processing cores and memory.

They are also rated to run 24/7 for long periods without suffering from instability or system crashes and are not meant to be worked on directly.

Key Differences between platforms

What’s all this about platforms? You just wanted to know the differences between a Desktop and Server CPU!

Bear with me for just a little bit longer – we’ll get to that 🙂

CPUs are unavoidably tied to their platform. You can’t slap a desktop CPU into a server platform and you can’t install a server CPU into a desktop platform.

The differences between Server and Desktop CPUs lie in their platform! Let’s take a look at the key platform differences:

Form Factor

One visually apparent difference between the desktop and server platforms is their form factor. Both the server and desktop platforms have standards for measuring the space the system occupies.

For desktop platforms, the typical form factors are XL-ATX, E-ATX, ATX, M-ATX, and M-ITX in order of their size. ATX is the most popular option for desktop PC systems, with M-ATX and M-ITX following suit.

Motherboard Form Factors and Sizes Compared

The E-ATX form factor is often found in workstation and enthusiast systems. The larger size lets them pack additional features, such as more PCIe and RAM Slots, while still being within the constraints of a desktop case.

Desktop cases also come in different form factors. They are categorized into Full Tower, Mid Tower, Mini Tower, and Small Form Factor (SFF). Compatibility with hardware for a particular case depends on its size, with full tower cases supporting most from factors while SFF cases only supporting M-ITX.

PC Case Size Comparison Graphic

Most servers come in either the tower or rackmount configurations. The tower configuration is similar to the desktop platform and is a good choice if you are working with a small number of servers.

Dell Tower Rack PC

Rackmount servers are made to use with standard 19” server racks, allowing you to stack servers vertically and save space. Apart from servers, you can also purchase rackmount storage arrays and network switches to add additional functionality to your setup.

HPE ProLiant DL380p Gen8 Server

The size of rackmount components is determined in units of height ranging from 1U up to 6U for general servers. Most server racks are 42U in height which allows you to fit quite a lot of hardware in a small amount of space.

Although there are some Server Motherboards that abide by the general Desktop PC Form-Factors, many are custom made to fit more efficiently into the Server Case you’ll be buying from the company.

Memory

Server platforms support ECC or Error Correction Code memory across their entire suite of processors. ECC support on desktop platforms is limited to a professional workstation, workstation, and a select number of consumer platforms.

On consumer platforms like AMD’s Ryzen on B550 and X570 motherboards, ECC support does exist but is not validated for server or workstation use, and compatibility varies by motherboard manufacturers.

ECC ram corrects memory corruption due to random bit flips, preventing system crashes and data corruption. This is important when you cannot afford system failures when using the computer 24/7 for an extended period.

Servers and professional workstation processors also support capacities of RAM that range in terabytes. For reference, a typical consumer platform will support no more than 128GB of memory.

The number of RAM channels available also varies between platforms. Server and Pro workstations have eight channels, while workstation platforms have four and consumer two. More memory channels improve the net bandwidth between RAM and the processor.

Multi-Processor Support

A feature unique to the server platform is the support for multiple processors. Multiple processors in a single system not only increases your core count but also gives you access to more memory and PCIe lanes in a single system.

With a single system having multiple processors, you save a lot of space and cost that separate systems would have occupied. This is great for e.g. render farms that require many processing cores in a limited space.

Expansion & Connectivity

Server and pro workstation platforms offer a large number of PCIe lanes. These PCIe lanes are necessary for adding expansion cards like GPUs, NVMe SSDs, SATA SSDs, HDDs, or network cards. To learn more, you can refer to our article on how many PCIe lanes you need.

Server platforms are highly versatile in their allocation of PCIe lanes. Do you need a large amount of NVMe drives? You have a server that does that, providing a full four lanes of PCIe connectivity per single drive.

Dell Poweredge r7525

Need a large amount of GPUs in a single system? You get that, too, with support for more GPUs than most desktop systems.

Nvidia Multi-GPU Server System

This just goes to show how versatile and easily configurable a server platform is. Servers are easily configurable with many GPUs, NVMe drives, or hard disks, all while keeping it compact.

Of course, servers aren’t optimized for quiet operation, so you won’t want to work directly on a server that sits under your desk. That’s why they are usually tucked away in a data center or separate room.

Professional workstations are also configurable, thanks to their abundance of x16 PCIe slots. However, they are not as versatile, mainly due to the space constraints of the desktop form factor, which may force you to use risers with expansion cards like GPUs to make the best use of the platform.

ASUS Pro WS WRX80E-Sage SE WIFI

Consumer systems have a lower number of PCIe lanes, which will limit your expansion to one or two GPUs and a couple of NVMe drives. Some specialized systems support several GPUs via a single 1x riser link for applications like mining, though it will severely impact performance in non-mining workloads.

What do CPUs have to do with platforms?

That was quite some detour into platforms. So what do CPUs have to do with platforms?

Processors are bound to a specific platform and will be compatible with only said platform. Take AMD’s consumer/workstation Ryzen and Epyc series, for example. There exists no Ryzen processor for servers nor any Epyc CPUs for desktops.

The CPU from each series is made for their own platform. Even processors identical on paper (e.g. same core counts and clocks) will differ significantly when taking into consideration the platform they work with.

What type of CPUs are bound to which platform?

Here’s a quick overview of what type of CPUs are bound to which platform and their typical core counts:

Desktop vs. Server CPUs

Key differences between Desktop CPUs and Server CPUs

As discussed above, processors within their platforms offer several features that help differentiate the two platforms. We will now focus on the actual differences between the processors.

Core Clocks

Desktop / consumer processors feature higher clock speeds making them an excellent option for active and single-threaded workloads that cannot be parallelized easily, like graphic design and large parts of video editing or gaming.

Intel and AMD also allow manual overclocking on many of their desktop chips, which provides additional performance at the cost of an increased power draw and stability. The thermal output of a processor core scales exponentially with its clock speed.

Desktop platforms, having a single processor in a well-ventilated system with options for large air and liquid cooling solutions, allow manufacturers to set higher core clocks without worrying about overheating.

Server platforms run in constrained environments where the only cooling method is high flow rate air over a small heatsink. Add to that multiple, high core count processors, and you need lower clock speeds to maintain temperatures for a stable, long-duration operation.

Lower clock speeds also reduce the power draw, which may not seem to have any benefit for a single CPU. However, when you plan to run hundreds or even thousands of processors, it will have profound implications, even for a few watts per processor.

Server processors also need to run 24/7 on high load, which significantly degrades their lifetime if run at high temperatures. That is why even low core-count server processors run at lower clock speeds than comparable desktop chips.

Core Count

While desktop platforms match servers in the maximum number of cores in a single processor, server processors have the unique advantage of being able to use multi-processor configurations.

Intel’s Xeon Scalable is an excellent example of how easily you can pack a single sever with many processing cores. Intel offers these processors in nodes that easily fit into a 2U chassis offering up to 224 cores in a single server.

Pricing Difference

Desktop processor pricing is straightforward, with the pricing generally being proportional to the processor’s clock speed and core count.

Server CPUs usually consist of highly binned components, meaning they run more stable and draw less power, making them more expensive even when compared to desktop CPUs that seem to have the same specs on paper.

The CPU has to have on-chip logic to access all the platform features as well, so it should come as no surprise that server CPUs that have access to e.g. more memory channels or more PCIe-Lanes have increased pricing – all other factors the same.

The right CPU for you: Server or Desktop processors

When choosing between a server and a desktop processor, it’s not just the processor that matters but the platform.

Once you go with a particular platform, switching to another will be expensive due to the lack of compatibility across platforms.

Choose the desktop platform if you plan to work on your PC or workstation from a desk actively. Although servers come in the tower configuration, they are not meant to be run as a standalone unit and will offer much less performance (low clock-speeds, etc.).

Go with the server platform if you plan on leaving it unattended. Servers are easily mountable on equipment racks and allow you to expand with additional servers, storage arrays, or network switches without taking much space.

Remember that rack-mounted servers are very loud, so they are not suitable for a home or work environment.

For applications like render farms that need a large amount of computing power, you can use the desktop platform as render-nodes if you need only a few of them. For large-scale operations, the space and energy savings of the server platform make rack-mounted servers the better option.

Our List of Recommended Processors:

FAQs

Rack server vs. Tower server: Which one is better?

Tower servers are more of an entry-level server for those looking to start with servers or in environments lacking server racks. Rack-mounted servers are the more mainstream option and are popular due to their ability to stack vertically in an equipment rack. These servers are also compatible with rack-mounted storage and network equipment.

Are server CPUs good for gaming?

Workloads like gaming and graphic design are highly optimized for single-threaded operation and greatly benefit from a high clocked processor. With server processors tuned towards stability and a lower power draw, they are not a good choice for gaming.

If you plan on hosting multiple VMs for gaming, then a server processor is a better choice due to their better support for virtualization.

Over to you

What kind of CPU are you thinking of buying? Let us know in the comments or ask us any questions you might have in our forum!