Whether you are building a new computer or replacing/upgrading your existing one, one of the most important considerations is the Power Supply Unit (PSU). PSUs are vital, as they provide the necessary energy for each component to operate efficiently while ensuring system stability and longevity. Here's a comprehensive guide on how to estimate the power required for your custom-built computer.

Before diving into calculations, it's essential to understand what contributes to a computer's total power consumption. Each component in your build, such as the CPU, GPU, motherboard, RAM, storage devices, and peripheral components, draws a certain amount of power during operation. The total power consumption of the system will influence the size of the PSU you need to purchase.

List your components

Begin by listing all the components you plan to include in your build. The primary components typically consist of:

• Central Processing Unit (CPU): The power requirement varies significantly among different models. Check the manufacturer's specifications (Thermal Design Power (TDP)) for this value.
• Graphic Processing Unit (GPU): This is often the most significant power consumer in a modern gaming PC. Again, manufacturers provide TDP ratings for graphics cards.
• Motherboard: While motherboards consume less power compared to CPUs and GPUs, it's still necessary to account for this.
• Memory (RAM): Each stick typically consumes between 2 and 5 watts of power.
• Storage: SSDs consume less power than HDDs, but still contribute to overall power consumption.
• Cooling systems: Fans and liquid cooling systems also draw power.
• Peripherals: Keyboards, mice, and other peripherals (especially lighting effects) can add to the power requirement.

Use an online PSU calculator

Using an online power supply calculator can simplify the process of estimating your total power needs. Various websites, see links below, offer interactive tools where you can input your components. These calculators take into consideration the specifications you provide and offer estimates based on average power consumption, including some headroom for future upgrades and peak loads.

Now, some online power supply calculators can estimate the power requirements given the specifications of the components. You can use these websites to calculate a rough estimate of the amount of power your computer will require. Here are a few online power supply calculators.

Newegg - Power Supply Calculator

PC builds - Power Supply Calculator

Cooler Master - Power Supply Calculator

Once you have a rough estimate of the power requirements for your components, add some extra headroom to ensure stable and reliable performance. A good rule of thumb is to choose a PSU that can provide at least 20 - 30% more power than your estimated requirements.

Calculate total wattage

If you prefer a manual method, follow these steps to calculate your system's wattage:

1. Find power ratings: Look up the power requirements for each component (generally available on manufacturer websites or retail listings). Write them down.
2. Total up power consumption: Sum the power ratings from each component.
   For example:
   - CPU: 95 watts
   - GPU: 300 watts
   - Motherboard: 75 watts
   - RAM: 16 watts (2 sticks x 8 watts each)
   - Storage: 10 watts (SSD and HDD combined)
   - Cooling: 20 watts (for 4 fans)
   Total power consumption = 95 + 300 + 75 + 16 + 10 + 20 = 516 watts
3. Add overhead: It's essential to add a safety margin to ensure stable performance. It is common practice is to add about 20-30% more power on top of your total wattage. This might look like:
   516 watts x 1.3 = 670.8 watts

Therefore, a 750-watt PSU would be a safe choice.

Consider efficiency ratings

When selecting a PSU, consider the efficiency rating, which indicates how well a power supply converts AC power from the wall outlet into DC power for the computer. PSUs are rated based on efficiency standards, such as the 80 PLUS standard. Here are the tiers:

• 80 PLUS Bronze: 82% efficiency at 20% and 100% load, 85% at 50% load.
• 80 PLUS Silver: 85% efficiency at 20% and 100% load, 88% at 50% load.
• 80 PLUS Gold: 87% efficiency at 20% and 100% load, 90% at 50% load.
• 80 PLUS Platinum: 90% efficiency at 20% and 100% load, 92% at 50% load.
• 80 PLUS Titanium: 90% efficiency at 10% and 100% load, 94% at 20% load.

Selecting a more efficient PSU can allow you to choose a PSU with slightly lower wattage, as it operates more effectively under load.

Plan for future upgrades

If you plan to upgrade your system in the coming years (e.g., adding more storage or upgrading your GPU), consider purchasing a PSU with a higher wattage than what you currently need. This foresight can save you money in the long run.

Estimating the power required for your custom-built computer is vital for ensuring system stability and efficiency. By carefully listing out your components, using online calculators or manual calculations, taking into account efficiency ratings, and planning for future upgrades, you can select the most suitable PSU for your build. A robust and reliable power supply is the backbone of any custom PC, and making the right choice can enhance not just performance, but also the longevity of your components.

Have you ever looked at a computer's specifications and wondered what that information meant? Technical jargon can be confusing. So here are some of the most commonly defined technical verbiage.

The vocabulary that the computer industry uses can be confusing at times. The different technical jargon can make your head spin. So here are the definitions for some of the most commonly used technical verbiage.

Motherboard

Chipset - An integrated circuit that controls data transfer functions - Chipsets are designed to work with specific CPUs and provide communication between the CPU and the other devices connected to the motherboard. Chipsets have a direct role in determining system performance.

Form Factor - The physical dimensions of a device or component - Motherboards come in various form factors, from the ultra-small mini-ITX to a full-size ATX. Always verify what motherboard form factor your computer case can hold.

CPU Socket - It holds the CPU and provides mechanical and electrical connection between the motherboard and processor - AMD and Intel use completely different socket types (Intel uses LGA, and AMD uses sWRX8, sTRX4, etc.). Be sure to confirm the CPU socket before purchasing a new motherboard.

Memory Slots - They hold memory modules and provide mechanical and electrical connections between the motherboard and memory - Desktop and laptop motherboards usually have 2 - 4 memory slots. Server motherboards can have up to 32 memory slots.

Central Processing Unit (CPU)

Core - A Core is a separate processing unit inside the CPU that executes the instructions that the user initiates, such as running programs and completing complex calculations - All modern CPUs have multiple cores to run several processes simultaneously.

Thread - A thread is a sequence of programmed instructions - You will usually find two (2) Threads using one (1) Core. This is where the term multithread comes from.

Generation - A CPU Generation is the average time between product release cycles - This period is usually one (1) year.

Clock Rate - The frequency/speed that the CPU operates at - The higher the clock rate is, the faster a CPU can process instructions.

Memory

Type - The physical interface that connects the memory module to the motherboard - Memory modules come in various types, from the standard DDR (Double Data Rate) to Double Data Rate 5 (DDR5).

Speed - The frequency at which the memory operates - Memory speed is measured by transfers per second. For example, PC5-38400 can handle 4,800 transfers per second.

Capacity - The amount of data the memory module can hold - The capacity of a memory module is always a multiple of 2 (2, 4, 8,16, 32, 64, etc.).

Column Address Strobe (CAS) Latency - The delay in clock cycles it takes between when data is read and when it is available for use - When selecting memory, always use modules with the same CAS latency. Using memory modules that have different CAS latency can cause system instability.

Hard Disk Drive (HDD)

Form Factor - The physical dimensions of a device or component - HDDs come in 3.5" or 2.5" widths. The height of 2.5" HDDs can vary between 7MM and 9MM.

Capacity - The amount of data the drive can hold - HDD capacity can vary from Gigabytes (GB) to Terabytes (TB).

Interface - The physical connection between the motherboard and HDD - All HDDs utilize a SATA interface connection.

Revolutions Per Minute (RPM) - The speed at which the platters inside of an HDD spins - The faster the HDD platter spins, the quicker data is transferred.

Cache - The embedded memory that acts as a buffer between the motherboard and drive - Normally, the larger the cache, the better performance you will get from the HDD.

Solid State Drive (SSD)

Form Factor - The physical dimensions of a device or component - SSDs come in various physical forms (sizes); 2.5", M.2, and U.2. M.2 SSDs also come in various widths and lengths. The code that follows M.2 is that particular drive's width and length in millimeters. For example, an M.2 2280 has a width of 22MM and a length of 80MM.

Capacity - The amount of data the drive can hold - SSD capacity can vary from Gigabytes (GB) to Terabytes (TB).

Interface - The physical connection between the motherboard and SSD - There are primarily three (3) types of interfaces; SATA 3, PCI-e 3, and NVMe. What type of interface is determined by the form factor. 2.5" drives use SATA 3, and M.2 drives use either PCI-e 3 or NVMe. M.2 drives also have key notches: B key, M key, or both.

Memory Type - Most SSDs use NVMe (Non-Volatile Memory Express) - NVMe has become the default standard memory for most SSDs produced.

Graphics Processing Unit (GPU)

Power Requirements - The amount of power required to operate the GPU - Most GPUs require one (1) PCIe 6 or 8-pin power connector, with some high-end graphic cards requiring a 16-pin PCIe 5 connector.

Interface - The physical connection between the motherboard and graphics card - Most GPUs require a PCIe x16 slot using the same PCIe version (3.0, 4.0, 5.0, etc.) as the motherboard.

Memory - The physical amount of memory embedded on the graphics card - Graphics cards use a type of memory designed explicitly for processing graphics called Graphics Double Data Rate (GDDR). There are multiple versions of GDDR, including GDDR5, GDDR6, and GDDR7.

Speed - The frequency at which the GPU operates - GPU clock speed is how many processing cycles it can execute in a second.

Power Supply Unit (PSU)

Type - PSU types are based on the different computer case form factors - The majority of PSUs are ATX form factor, as it is the most popular case type.

Power Output - The rated maximum wattage that a PSU can deliver - A PSU output can range from 400W to over 1500W.

Modular / Non-Modular - The type of physical connection for the different power cables leading to the various devices - Non-modular PSUs have all of the device connections physically attached; modular PSUs have separate cables for each type of device, so you only have to connect the cables for the devices you need to power.

Being a computer technician, there is one question that I seem to get asked more than any other: "I am looking for a new computer. What do you recommend?". I then spend several minutes (sometimes hours) discussing the various computer configurations. So here is a list of things to look for when buying a new computer.

When it comes to computers, you can get them in hundreds of different configurations. Should you get a laptop or a desktop? Or maybe an all-in-one? These are some of the questions you must ask yourself when looking to get a new computer.

So, I thought I would take the time to share with you what I usually tell my customers. So grab something to drink and a pen and paper to take notes. This might be a long article.

Computer: Should I get a laptop, desktop, or all-in-one?

This question is quickly answered with the Form Follows Function principle. If you need to use your computer in different locations, you will need to get a laptop. If you are going to use your computer in just one place, then a desktop or all-in-one should fill the bill.

Laptops

If you are thinking about getting a laptop computer, there are a few things to keep in mind. If you take a few precautions with your laptop, it can last a long time. I have a netbook that is over ten (10) years old and still looks and runs like it's brand new.

Since laptops are portable, they tend to get damaged more often than desktops or all-in-one computers. The most common damage I see is broken hinge mounts and liquid spills. In over twenty years of repairing laptops, I have only seen one broken hinge; it's always the mounting points that fail.

Once liquid enters a laptop, it will run whereever gravity takes it. And no matter how well you dry it out, some damage will eventually appear. And I am just talking about water here as other liquids, such as wine or juice, contain sugars and acids.

I once had a laptop in the shop that had wine spilled on it. When I started disassembling it, I noticed that the flat cables used to connect the different components inside the laptop had begun to deteriorate. The wires were dissolving from the acidity in the wine.

Desktops

Desktop computers have been the mainstay of the computer form for decades, and they are the preferred style of a computer for business use. With external connections for USB devices, monitors, wired networking, and audio, the configurations are endless.

However, desktop computers come in different forms and are not all created equal. For example, standard ATX, Mini-ATX, and ITX (motherboard form factor) based desktop computers use IEEE (Institute of Electrical and Electronics Engineers) form standards for computer components.

What this means is that internal components such as power supplies, hard drives, graphic cards, and memory modules are all the same for each of these styles of desktop computers.

And then there is the SSF (Small Form Factor) desktop computer. These use the same style of memory modules as standard desktop systems but use low-profile expansion cards, like graphics cards.

SSF systems also use smaller and lower output power supplies, usually explicitly made to the computer manufacturer's specifications. The lower output power supplies can be an issue when upgrading components.

For example, a customer wanted to upgrade the memory and graphics card in an SSF computer, but it only had a 250-watt power supply. Since everything inside of a computer takes wattage, including memory, I ended up having to find a low-profile graphics card that used under 30 watts of power.

However, some desktop computers have a downside, which is the case's size. Gaming computers usually have huge cases to accommodate cooling fans and liquid CPU coolers. High-power systems generate a relatively large amount of heat.

And, of course, if you are going to have multiple monitors, those will take up a good amount of space, too. I built a system for a customer with six (6) monitors, two rows of three. The system was almost eight (8) feet wide with the monitor array, desktop computer, keyboard, and mouse.

All-in-one

This style of computer is excellent for people that do not have room for separate components (a computer and a monitor). You can get a pretty-good size screen and all of the connections (USB ports, wired network port, and sometimes an external monitor port).

Now, all-in-one computers come with and without touch screen functions. When it comes to touch screens, you have to remember that you will be extending your arm out to use it.

This can make your shoulder hurt after using it for an extended amount of time. You have to ask yourself if getting the touch screen feature is worth the additional cost.

There is also a little-known secret about all-in-one computers that nobody tells you about: they are hybrid systems. Quite simply, they are a combination of laptop and desktop components.

I have worked on quite a few all-in-one computers and found some will use laptop-style memory & drives, some will use desktop-style memory and drives, and some a combination of both.

And heaven forbid you have to replace the screen in an all-in-one computer. Most of the time, you have to completely disassemble them to get the exact model number of the display.

The last all-in-one computer I worked on had six (6) different possible model numbers for the replacement display. It depended on what company had supplied the screen for the system when it was built.

Drive(s): HDD, SSHD, or SSD?

When you are shopping for a new computer, a lot of times, the description you get from the seller lacks some specific details. Sure they will tell you how much storage the machine has, but do they tell you what kind of drive the storage is?

For low-priced computers, sellers will usually just say something like, 'XXXGB's of storage can hold a gazillion photos'. It is only when you get into the mid to upper price range that sellers start to tell you what kind of storage a computer has (HDD, SSD, etc.). So the first thing I want to do is explain the different types of drives.

HDD (Hard Disk Drive)

HDDs offer larger capacity at a lower cost but have a slower read/write speed. HDDs are perfect for the average computer user who just wants to surf the web, check e-mail, and store photos from their phone. They come in two (2) different forms, 2.5" and 3.5", and connect to the computer using a SATA (Serial AT Attachment) interface, which determines the input/output speed. The upside to HDDs is that when they start to fail, you usually get some type of warning and have time to transfer/recover data from them.

SSHD (Solid State Hybrid Drive)

SSHDs offer the capacity of HDDs with faster read / write speed. As the name implies, these drives are hybrid, which means they are a combination of spinning disk(s) and flash memory. The memory acts as a cache for the data stored on the disk(s). As you use these drives, they learn where the most frequently used data is stored and can access it more quickly than a standard HDD. SSHDs also come in two (2) different forms, 2.5" and 3.5", and connect to the computer using a SATA interface. The downside of SSHDs is that when they fail, it is usually the memory portion of the drive that dies. This makes transferring/recovering the data stored on it a little more complicated but possible.

SSD (Solid State Drive)

SSDs offer extremely fast read/write speeds but can be on the expensive side for larger capacities. SSDs are a collection of flash memory chips and make no noise when running. They are also more resistant to shock and are a better choice for laptop computers. SSDs also come in multiple different forms and interfaces. Regarding SSDs, the most important thing to look for is the interface it uses. It is the interface that determines the read/write speed. SATA interfaces can have a transfer rate of 6GB per second. M.2 interfaces can have a transfer rate of 32GB per second. The downside of SSDs is when they fail, it is tough to recover the data stored on them. So if the computer you are looking at buying has an SSD, perform a regular backup of it.

A good rule of thumb when determining what type of drive a computer might have is to remember that if the size is under 500GB, it is probably an SSD. Drive manufacturers no longer make HDDs or SSHDs smaller than 500GB. Now that we have covered the types of drives let us take a quick look at how they can be used and configured.

Single-drive computers - All-in-one computers and low-priced desktops and laptops usually have only one drive. Also, ultra-thin laptops often have either one thin profile HDD, SSHD (7MM SATA) or SSD (7MM SATA or M.2) drive.

Multiple drive computers - Mid to high-priced desktop and laptop computers can come with numerous drives. You usually see gaming computers with multiple drives that have a smaller, 500GB to 1TB SSD (usually an M.2) for the operating system/programs and a larger HDD, 2TB or larger, for data storage.

I have seen some gaming computers with two (2) SSDs set up in a RAID (Redundant Array of Inexpensive Disks) 0/1 configuration. These are rare, but they are on the market. So keep your eye out for them.

While we are on the subject of multiple drive configurations, we need to talk about Intel Optane. You may see Intel Optane listed as part of the storage specification on a new computer.

Now, Intel Optane is similar to the flash memory inside SSHD drives. It can cache the most frequently used files and programs on a drive that it is paired with and speed up reading and writing to that drive. Intel Optane uses an M.2 interface and works best when paired up with a drive, either an HDD or SSD, that uses a SATA interface.

Intel Optane will not improve the performance of drives that use an M.2 interface. I had a customer who had me set up an Intel Optane device paired with an M.2 SSD. Believe it or not, the read-and-write performance went down. Definitely not a good choice.

Processor: What brand and type should I get?

There are two main CPU (Central Processing Unit) manufacturers, AMD and Intel, and both have pros and cons. Intel CPUs usually are a little bit more expensive, and AMD CPUs are infamous for being able to be over-clocked.

All modern CPUs have multiple processing units called cores. The more cores a CPU has, the more data it can process at one time. Then, you have the frequency (speed) at which the CPU processes the data.

But since most CPU's run at a frequency between 3 GHz and 5 GHz, the amount of time you gain using a 5 GHz CPU over a 3 GHz CPU is kind of irrelevant. So it comes down to how many cores do you need.

Using Intel CPUs as an example, the basic Intel I3 processor has two cores and works well for running one program at a time, like e-mail, writing documents, and surfing the Internet. However, it does not work very well when you try multi-tasking with Adobe Photoshop and Autodesk Revit.

On the other end of the Intel CPUs, you have the Intel I9 processor line, which can have up to 10 cores. These processors can handle running multiple programs simultaneously and are the preferred CPU for 3D rendering. But remember, the more cores a processor has, the more money it costs.

Memory: How much should I get?

When it comes to the amount of memory you should get in a new computer, it just comes down to the question, "What are you going to use your computer for?".

The first thing you have to take into consideration is the operating system. Every computer nowadays has a 64-bit processor, and the operating system uses a portion of the memory just for itself.

For example, a 64-bit version of Windows 11 requires 2 Gigabytes of memory just for itself. That doesn't include any other programs. If your computer does not have a separate GPU (Graphic Processor Unit), then the onboard IGPU (Integrated Graphics Processing Unit) would also use some of the system memory.

The bare minimum amount of memory I recommend is 8 Gigabytes, but 16 or 32 Gigabytes is more of a standard amount. 64 gigabytes and higher is nice, but it will add more to the cost of the computer.

Video/graphics card: What should I look for?

Here again, it is all about what you are going to use your computer for. Each type of computer (laptop. desktop and all-in-one) has its pros and cons when it comes to graphics.

All-in-one systems are meant for everyday computing, spreadsheets, e-mail, and surfing the Internet. They usually just have an onboard IGPU that uses the system memory.

Laptop and desktop computers usually come standard with an onboard IGPU and can also include a separate GPU that has its own individual memory. If you are looking for a gaming or 3D rendering computer, you will want a separate GPU.

Now, features available for separate GPUs will differ from laptop to desktop computers. You will find that you get a better selection of GPUs with desktop computers than with laptops. The reason is desktops use PCI-e expansion slots for adding separate GPUs.

For more about expansion cards, check out the following article.

How to add an expansion card to your desktop computer

Either way, if you are looking for a computer with a high-performance GPU, check the requirements of the software you want to run. That will give you the guidance for what GPU features you need.

On a side note, I have had to troubleshoot display issues with laptops that have an IGPU and GPU. With these types of laptops, the IGPU and the GPU run simultaneously and switch between the two depending on the demands of the programs running.

Sometimes these types of laptops will experience crashing when switching between intense graphic programs like games and standard applications like web browsers. The easy fix is to set the GPU as the default graphic processor for all programs.

Monitor: Single or multiple?

I usually tell customers to get the largest size that space will allow. With the display resolutions constantly increasing, having a monitor that can handle them is essential. You will likely own this monitor for over a decade, so you should consider any future use.

When shopping for a monitor, you have to keep in mind how it is going to connect to your computer. You will need to check the available video connections on your computer and get the same type on the monitor. Here is a link to an article with images of the most popular video connectors.

The most common computer video display connectors

Now two types of video connectors also include audio, HDMI, and DisplayPort. So if you plan on using one of these video types to connect your new monitor, make sure that the monitor you purchase has built-in speakers.

If you use an HDMI connection, you can also use a television as a monitor. The resolution may be lower than that of a regular monitor, but you could use it as a television, too. I built a computer with an HDMI graphics card just for my home entertainment system.

Keep in mind that any monitor you buy may not come with the correct video cable to connect it to your computer. Getting a cable at the same time you purchase the monitor could save you a lot of frustration when it comes to setting up the new computer.

And keep the receipt for any cables handy, just in case the new monitor does include the correct one. I would rather have to return a cable at my leisure than have to run out to get one to finish the setup. As the old saying goes, 'An ounce of prevention is worth a pound of cure'.

What if the computer you are looking at buying can support more than one monitor? If you are going to go with multiple monitors, I recommend getting the same make and model for each one and, if possible, buying them at the same time. That way, you get monitors manufactured around the same time as each other and have matching specifications.

Once you get your new computer set up, you should do a few things first. Here is an article that discusses those things in detail.

Five things you should do first when you get a new computer

When doing computer repair for a living, there is one thing I do pretty often: replacing and upgrading computer components. Whether it be replacing a drive or installing a new graphics card, there is always something you need to consider. So here are a few things you should ask yourself when selecting computer components.

Things to consider when replacing or upgrading your motherboard

Form factor

• What form factor size does your existing case support?
  If the motherboard you are looking at getting is ATX and your present case only has space and stand-offs for a mini-ATX motherboard, you will not be able to install the new motherboard.
• Do you have any of the extra parts that came with the case, including stand-offs for the motherboard?
  If you are replacing a mini-ATX motherboard with an ATX motherboard and your case is large enough for it, do you have the stand-offs and screws for the extra mounting points that the new ATX motherboard will require?
• Do you have the installation media for the operating system and all your programs?
  When you change out a motherboard, unless it is from the same manufacturer and same model line, odds are you will need to perform a clean installation of the operating system and your apps. If you try to use the existing operating system currently installed with a new motherboard, you are more than likely to get all sorts of errors. Be prepared to reinstall the OS and apps.

CPU socket

• What is the socket type of your existing CPU?
  You cannot use an LGA1150 processor in an LGA1151 socket.
• Will the new motherboard you're thinking about getting support your existing processor?
  You will need to do your research on the motherboard you are thinking about getting. If you cannot find the information online, give the manufacturer a call. There is nothing worse than getting a motherboard that you cannot use.

Memory slot(s)

• Does the motherboard you're considering getting support your existing memory modules?
  Again, do your research. You have to make sure that everything will go smoothly when you do the upgrade.
• Or are you going to need to get new memory modules?
  If you find out that you will need new memory modules, buy them in pairs (twin-pack, quad-pack). Try to avoid mixing different memory modules if you can. You will also find buying them in twin or quad-packs cheaper than single modules.

Expansion slots (PCI-e)

• What do you currently have for expansion cards?
  These include graphic card(s), RAID controller card(s), M.2 adapter card(s), Wi-Fi/ethernet card(s), etc..
• And what type of expansion slot(s) do they use (PCI-e x16, PCI-e x4, PCI-e x1)?
  Make a note about all of the different PCI-e slots that are used on your existing motherboard, and reference it when you are looking at a new motherboard.

M.2 Slot(s)

• If your existing mother has M.2 slot(s) and you use them, what form factor, key notches, and interface do they utilize?
  M.2 2242, M.2 2260, M.2 2280? B key, M key, or both? SATA 3, PCI-e 3, or NVMe?

Internal USB connections

• What type of USB headers does your current motherboard have?
  USB 2.0, USB 3.0, USB 3.1 Gen 1 or USB 3.1 Gen 2.

Internal drive connectors

• What type of internal drive connectors does your current motherboard have?
  SATA, SATA Express or U.2?

Power connector

• What type of power connector(s) and how many does the motherboard you are thinking about getting have (4-pin or 8-pin ATX 12V)?
  Does your existing power supply have the correct amount of connector(s)?

Related articles
Tips for choosing the right motherboard for your custom-built computer

Things to consider when replacing or upgrading your processor / CPU

Socket type

• What socket type does your current motherboard have (LGA 1151, LGA 2011, AMD AM5, etc.)?
  Remember that you cannot use an LGA1150 processor in an LGA1151 socket.

Motherboard compatibility

• What processors does your current motherboard support?
  You will need to do your research on your existing motherboard. If you cannot find the information online, give the manufacturer a call. You may need to update the BIOS on your current motherboard to run the new processor you are considering getting.

Things to consider when replacing or upgrading your CPU cooler

The space inside of case

• Does your present case have room for an upgraded CPU cooler?
  If you are thinking of air cooling, do you have enough space on top of the CPU for it? If you're thinking about liquid cooling, do you have the correct mounting holes for it? And will you need to replace any of the existing case fan(s) to accommodate a new CPU cooler?
• Does your motherboard have all the connectors for running a liquid CPU cooler?
  Some liquid coolers require an onboard USB header to function correctly. Also, does your motherboard have any special liquid cooler fan headers?

Related articles
Tips for choosing the right CPU cooler for your custom-built computer

Things to consider when replacing or upgrading your graphics card / GPU

Slot version

• What version of PCI-e slot (3.0, 4.0, 5.0) does your current motherboard have?
  To answer this question, you will need to reference the motherboard manual or specifications online. If you have a problem finding this information, just contact the motherboard manufacturer.
• What PCI-e version is the graphics card you are looking at getting?
  Again, to answer this question, reference the graphic card manual or specifications online. If you have trouble finding this information, just contact the graphics card manufacturer. If the PCI-e slot on your motherboard is version 3 and the graphics card you are looking at getting is version 4, you will have a problem.

Power connection(s)

• Does the graphics card you are looking at getting require a separate PCI-e power connector(s)? If so, are they 6 or 8-pin PCI-e or 12+4 PCI-e 5.0 connector(s), and how many does it need?
  You should be able to find this information on the vendor or manufacturer's website. The information should also be on the outside of the box.
• Does your current power supply have all of the proper PCI-e connector(s) for it?
  Some lower-wattage power supplies have only 6-pin PCI-e connectors. Visually check your existing power supply for the type and quantity of PCI-e power connectors.

Related articles
Tips for choosing the right graphics card for your custom-built computer

Things to consider when replacing or upgrading your memory

Slot type and speed

• What slot type and memory speed does your existing motherboard support (DDR3 2400, DDR4 4200, DDR5 6400, etc.)?
  To answer this question, you will need to reference the motherboard manual or specifications online. If you have a problem finding this information, just contact the motherboard manufacturer.

Existing memory compatibly

• Are you going to add more memory to your current memory?
  The one thing you want to try and avoid when adding memory is incompatibility with existing memory. If you plan on adding a couple more memory modules, try to use your current memory's exact make and model. Even though memory from different manufacturers may be the same slot and speed type, their clock timings can differ. So, using the same make and model of memory in all slots is always recommended. If you can't, make sure you match the memory timing of your existing memory.

Related articles
How to upgrade or add more memory to your computer

Things to consider when replacing or upgrading your drive

Form factor and size

• What size and form factor drive(s) are you looking at getting?
  If you are replacing an existing drive, you should go with one that is the same form factor (3.5", 2.5", M.2, or U.2) and the same size (GB's, TB's) or larger than your existing drive. If you are upgrading your drive to a different form factor (SSD, HDD, or U.2), you need to make sure your current case has a place to mount the other kind of drive (3.5" or 2.5"). If you are upgrading your drive to a different form factor (M.2, mSATA), you need to make sure your existing motherboard has the correct form factor (M.2 2242, M.2 2260, M.2 2280), key notches (B key, M key or both) and interface (SATA 3, PCI-e 3 or NVMe) as the drive you are looking at getting. If you want an M.2 or mSATA and your motherboard does not have the appropriate slot, you will need to use an expansion card.

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Things to consider when replacing or upgrading your case

Motherboard Form Factor (micro-ATX, ATX, ITX, etc.)

• What is the form factor of your existing case?
  If the case you are looking at getting is designed for a mini-ATX motherboard, you will not get a standard ATX motherboard to fit in it. Check the case manufacturer's website to verify the motherboard form factors that will fit in it.

CPU fan

• Does the case you are looking at getting have enough space for your existing CPU fan?
  There is nothing worse than getting the motherboard, CPU, and cooler installed in a new case only to find out that you cannot get the side of the case on. Double-check all dimensions.

Peripheral/expansion

• Does it have enough front panel connectors for the onboard headers of the motherboard?
  It sucks having USB 3.0 header(s) on the motherboard and not having any or enough connectors on the front of the case.
• If you have a DVD or BD drive, does it have a 5.25" drive bay in front for it?
  Many cases nowadays do not have 5.25" drive bays. If you have a 5.25" drive or drives (CD, DVD, BD), you will need to double-check the case you are looking at getting.

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