The complete guide to upgrading your PC

11th Jul 2010 | 11:00

The complete guide to upgrading your PC

How to upgrade your PC's memory, processor, graphics, cooling and more

Getting ready to upgrade your PC

Everyone knows the feeling. Your PC has become slow and unresponsive, and it's getting rather noisy too. All around you are adverts for fast new machines – PCs groaning with cutting-edge components and fancy new features; machines untouched and factory fresh.

It's easy to wilt under this kind of pressure and give into the new PC dream – but luckily we're here to help you to renew your willpower and stand firm against such temptations!

We have happy news: a few well-targeted and cost-effective upgrades can transform your flagging PC into the machine of your dreams. So why has your machine got so slow?

Well, just as time can be particularly punishing to Windows' boot time, so it can ravage the hardware in your system. Dust can clog fans and obstruct airflow, overheating your components and bringing their efficiency down.

Add to this physical consequence of time's passing the fact that in the years your PC has been sitting in your home, clever-clogs developers have continued to plug away at their work, creating faster components than those in your machine were even when they were factory-fresh. We're sure you can see how the problem has arisen.

Refresh your system

This means the best way to speed up your PC is to give it a spring clean and identify the components worth upgrading. In general terms, a PC will last you for a couple of years before you either have to do a major upgrade or piece together enough smaller ones to make the system continue to be fast enough for everyday use.

Which upgrades are best for you is ultimately defined by what you use your machine for. If you're into video editing and production then a healthy amount of memory will make moving clips around that much smoother, while a faster processor will render your effects and final edits quicker. An SSD will boost program loading times as well as your OS's boot time.

Audiophiles have similar needs, but they should also keep an eye on how much noise the system is making. Designers benefit from an overall system refit that focuses on an SSD and embraces the current low in memory pricing.

The programmers among you will be hankering after more memory as well, along with access to newer motherboard technologies such as USB 3.0 and SATA 6Gb/s – purely for research, of course.

Gamers will see the biggest boost from a graphics card upgrade, because while the promise of multithreaded gaming is closer than ever, the graphics card is still the biggest bottleneck in most systems. And two years is a long time in the graphics card business – we've seen the release of not only affordable DirectX 10 cards in that time, but a new breed of cutting-edge DirectX 11 hardware as well.

Over the page we'll explain how to work out which components you need to upgrade, talk you through how to do it, and reveal how a tissue can help speed up existing hardware.

Upgrade your RAM

Once your memory was enough to power your system, but application demands have risen

Memory has fallen in price, and that alone has made putting more RAM into our systems a realistic option. More memory means less time spent caching out to the hard drive, making your PC more responsive.

Memory pricing can still be volatile, but in general it has never been so affordable to upgrade. There is one exception to this rule, though – DDR3 memory. Despite old DDR2 dropping in price, the newer stuff's cost has stayed stubbornly high.

However, the relentless march of technology means that DDR3 will get cheaper. With all this in mind, we recommend that 4GB of RAM is the target for most machines, and if you're running a triple-channel Core i7, then go for 6GB. Going beyond this isn't a complete waste of money, although memory isn't free – so the current sweet spot is a 2 or 3GB upgrade.

Memory matchmaking

To make an effective upgrade, you should add an identical pair to your existing sticks – assuming that you have an identical pair in your machine already. So if you've got a pair of 1GB 800MHz DDR2 sticks running at 5-5-5-18 latencies, say, then ideally you'd buy an identical pair and drop them in alongside.

These sticks needn't be from the same manufacturer, but they do need to have the same latencies and operating frequencies. Matched capacities will also make life easier.

Most memory modules ship with a sticker on the side detailing exactly what their timings are, so physically examining the modules should be all you need to do in order to get the right sticks.

If you bought your machine prebuilt however, you may find that the sticker is missing, or is unreadable. Thankfully, utilities such as CPU-Z can reveal everything that you need to know about the memory in your machine.

If you're having problems, then online tools such as Kingston's Memory Search can help when it comes to spotting what memory has been used by some of the more popular system builders.

There is a problem with upgrading to 4GB of course, and that is the limit of addressable memory offered by 32-bit operating systems. Essentially, in any 32-bit version of Windows, you won't see the whole 4GB. The solution is to upgrade Windows to a 64-bit rendition. Happily this may not cost you anything, depending on your version of the OS.

How to: Pick and install the right RAM

1. Investigate existing RAM


Use CPU-Z to check your current memory settings. There are two tabs that you need to look at – Memory and SPD. The Memory tab shows how fast your RAM is currently running and what timings it's using. The SPD tab shows you what the memory stick in each slot is capable of.

The key factors here are the module size and the JEDEC timing settings for the frequency at which the memory is currently running. This information is given for each memory slot, and hopefully you should have some slots free.

2. Confirm the part number


CPU-Z will tell you what sort of RAM your machine is using, but it's worth physically checking before you order. Hold the memory at the edges and ease out the clips that hold the stick in place at the ends.

You should now be able to remove it and have a gander at its sticker. Just searching for the part number can be enough to find replacements, although this can mean you miss out on better deals.

You don't have to buy matched pairs for normal use, either – but make sure you get the same frequency and latencies.

3. Install, then check the BIOS


Memory installation is fairly straightforward, possibly hampered only by the amount of room in your case. If you need to unplug drive cables or remove the graphics card to get better access, do so – it beats damaging the memory.

Once you've populated the bays, restart the machine and head into your machine's CMOS configuration utility. You should find that the memory settings are fairly well signposted. Ensure that the timings are correct (use SPD timings by default), save the changes and restart your PC to get going.

Understanding graphics cards

If your games aren't running as smoothly as you'd like, upgrading your graphics cards should give them a boost

You shouldn't worry about your graphics card unless you play games. The modern integrated graphics chips found on motherboards are more than capable of handling 2D graphics needs, and cheaper add-in cards are also well up to the task.

Unless you're a gamer, the only time you need to look at upgrading is if your current model develops a fault. If this is the case, passively cooled entry-level cards (like the Asus HD 4350) boast 256MB of onboard memory, will run Aero smoothly in Windows 7 and can be picked up for as little as £24. This new generation packs a healthy triumvirate of connection options, too, with the relatively new HDMI outputs being backed up by legacy DVI and VGA connectors.

If you do have a penchant for gaming, things get a little more complex, if only due to the sheer number of cards available. Upgrading gamers often find themselves plagued by the perennial problem of trying to work out which card offers the best performance at the most reasonable price point.

Benchmark its grunt

Performance is key for any such upgrade, and you should compare your current card against any upgrade using industry standard benchmarks in order to ascertain if it's worth the outlay. By way of example, the venerable 3DMark06 from Futuremark rates the Radeon HD 5850 at 19,670.

You can find out how your card compares by downloading the benchmark and testing your system. Ideally you should benchmark using your game of choice, but finding comparisons isn't always easy.

How to: Update video drivers properly

1. Out with the old


Driver updates are a regular occurrence for many gamers, but they can introduce problems if the detritus from one set is left over after the upgrade. The solution is to remove every last trace of the previous drivers before starting.

Grab a copy of Driver Sweeper. Uninstall your current graphics driver set and then run Driver Sweeper to scour your system for any left-over references. Select all of the files and Registry entries the utility finds and then hit the 'Clean' button to purge your system.

2. In with the new


Restart your machine and run Driver Sweeper again to make sure that everything has gone. Next, download the latest drivers for your graphics card from or

Once you've done that, install them. If you have any problems with the new drivers then you should be able to roll back to the old ones – both manufacturers keep older drivers available. You should find that the new drivers will improve performance and stability in more recent games – especially if you run an SLI or CrossFire pairing.

Cool down, speed up

Getting a little more power out of your CPU can be as easy as banishing the dust from its case

Modern processors feature thermal cut-outs that throttle back the core frequency if the CPU's temperature gets too high. In other words, if you don't maintain sufficient cooling to the processor, you won't get the full performance out of it.

The temperature at which your CPU will start easing back varies by manufacturer and model. The Core 2 Duo E4400 has a maximum temperature of 61.4C, while the E4500 operates at up to 73.3C. Online data sheets for your processor will contain this information.

How to: Optimise your cooling

1. Check current temperatures


Before taking anything out of your machine, check how hot your processor is running. CPU Hardware Monitor provides detailed temperature information for your CPU cores and motherboard, and is free.

Take a reading with nothing else running (idle) and then when another running Super Pi (under load). Then check these figures against your CPU's datasheet.

2. Remove your existing fan


Removing processor fans is easy. For Intel components, unlock the four holding pins by turning them clockwise; you're then able to pull the whole thing out.

The fans that ship with standard AMD processors are easy to remove – lift and release the holding arm and then ease the cooler out. Don't forget to unplug the fan power cable before removing it completely.

3. Wipe off the thermal grease


Before placing the cooler on your workbench, clean off the existing thermal grease using a tissue and possibly a little solvent.

You will need some more thermal grease later though, so if you don't have any new stuff , it's best to place the cooler on a piece of paper without cleaning it (so that no impurities are mixed into the existing grease). Remove the CPU and clean the grease off that too.

4. Clean the blades


Use a piece of tissue or a soft brush to clean along the line of the fan blade. Don't push too hard, though, as these can break off under pressure.

Dust tends to accumulate on the top of the fan blades, so it shouldn't be too hard to clean away. If your fan is in a housing, take it apart if needed so that you can get better access to the heatsink and the fan.

5. Add new thermal grease


Put the CPU back into its socket and apply a new layer of thermal grease to the top of the processor.

Remember, your aim is to have a very fine layer to fill in any gaps between the CPU and heatsink, not to make a grease sandwich. A small blob should be sufficient. If you didn't remove the old thermal grease, check how much is on the processor and remove any if possible.

6. Reseat and retest


Put the cooler back in its home and wiggle it in place a little to make sure that the thermal grease is spread evenly between the cooler and CPU. Next, clip the retaining arms or pins back into place and reconnect the fan to your system.

Boot your machine and run the same tests that you originally did. If your CPU is still running too hot then a new cooler is needed.

Replacing the CPU

A new processor can give your system a new lease of life, but how do you pick which CPU to upgrade to?

CPUs are fairly easy to upgrade in theory, but buying the newest model available often means a complete reworking of your current machine. It's all very well recognising how powerful the Intel Core i7 X980 is, but you won't be able to just drop it into your Phenom rig and hope for the best.

There are two ways of tackling a potential processor upgrade, and both have pros and cons. The first is to replace your current processor with the fastest pin-compatible option currently out there. This is the most affordable type of CPU upgrade, as you can generally get away with buying the best original equipment manufacturer (OEM) model and simply replacing your current chip like-for-like.

Unfortunately this usually only results in a small speed boost, unless you are making the jump from a dual-core chip up to a three-or four-core offering.

AMD's decision to focus on a single socket for its desktop processors means its chips are easier to upgrade, as there are some fairly large upgrades available that use the same packaging. Visit your motherboard manufacturer's site to see whether your existing board supports the CPU you are looking at, or if there is a BIOS update that will add support for that chip before buying.

You'll need to bear in mind that if the new chip supports DDR3 and your motherboard only has DDR2 sockets, then you will be limited to using the older standard. If your motherboard has both types of memory slot present, upgrade the RAM for a further boost.

Screw the expense

The second option generally means that you ignore your existing hardware and simply go for the best processor available, picking up the requisite motherboard, memory and possibly graphics card as needed. This option is generally constrained by expense, because replacing multiple components is always going to be costly.

It will however result in the biggest performance boost to your system – especially if you use multi-threaded applications and are making the move to a multicore processor.

Upgrading your CPU can also mean that you need a new cooler, which is another potential expense, unless you pick a retail CPU that includes a compatible fan. If a pin-compatible CPU exists that will give your system a large performance boost then we would recommend you go with that, otherwise upgrading to the likes of the Core i5 is the sensible choice.

How to: Upgrade your CPU

1. Flash the BIOS

CPU upgrade 1

We'll assume that your motherboard needs a BIOS update before you can use your new CPU. Manufacturers provide updates in different ways, but all modern boards generally support flashing the BIOS from within Windows.

We would first recommend scouting the forums to make sure people aren't having problems with the latest BIOS. If you haven't updated for a while, you may need to install a string of them, but the general process is the same: flash the BIOS, reset to the defaults and check for updates. Rinse and repeat.

2. Remove the existing CPU

CPU upgrade 2

Before removing your CPU, benchmark your machine so you can see how much of a difference you've bought yourself. Synthetic benchmarks such as the X.264 video encoding test are particularly useful for comparing multithreaded upgrades.

Once you have figures to compare, power off your machine and give it a minute or two to cool. Unclip the processor's cooler, unplug the fan's power cable and ease it out of the way. Lift the lever holding the CPU in place and then pull the component free from the motherboard.

3. Install the new processor

CPU upgrade 3

If you've bought a retail CPU package, you can discard your old cooler because your new chip will have one that is designed for its thermal envelope.

Remove the chip from the packaging and ease it into the socket. Make sure that the chip is orientated correctly by lining up the lugs.

Add a little thermal paste to the top of the CPU and then place the cooler on top and clip it into place, wiggling the cooler first to make sure the grease is spread evenly. Connect the fan power cable, restart your PC and you're done.

Select the perfect motherboard

Upgrading your motherboard can be fiddly, and there are a terrifying number of options to pick from. We explain how to find your feet

Processors continue to absorb features traditionally the reserve of supporting chipsets, and a vision where the motherboard is merely a collection of sockets and ports isn't as outlandish as it once was.

Even so, for now motherboards still hold a vital role for our machines' capabilities, and as long as new technologies such as USB 3.0 and SATA 6Gb/s are developed, the motherboard still represents the most expedient way of getting those technologies out there. Is it worth upgrading your motherboard to get such features?

Unless you move a lot of data around and you can put a price on the time spent upgrading, we'd say no. Both SATA 6Gb/s and USB 3.0 are great features, and if you're going to upgrade your motherboard anyway then it makes sense to get access to these technologies, but it's not really viable as the main reason. You can buy add-in cards that will upgrade your machine without having to install a new board.

Bags of boards

So when is a good time to upgrade your motherboard? Generally, the time to do it is when you've decided on a platform change that revolves around a new processor. The Intel Core i5, for instance, will require that you buy a supporting H55/H57/P55 motherboard and a pair of DDR3 memory sticks to go with it.

Note that as Intel doesn't have a chipset that supports USB 3.0 or SATA 6Gb/s natively, such features are integrated using third-party ICs such as the NEC 720200 USB 3.0 controller and Marvell's 88SE9128 SATA 6GB/s offering.

The other factors worth bearing in mind when looking at any board are the options available for adding additional graphics cards, the quality of the onboard audio and the overclocking potential on offer. Now that memory controllers are integrated into the CPU, there's little performance difference between motherboards other than when they're overclocked, so this latter point is quickly becoming the defining ground between the likes of Gigabyte, Asus and MSI.

Even if you have no intention of doing this manually, the latest motherboards all boast automated systems that attempt to run the device faster than its specified speed.

When it comes to motherboard options, the core chipsets are surprisingly limited. For the top-end Intel Core i7, the X58 chipset is the only option, while for everyday computing the P55 does battle with the H55 and H57 variants. These boards support the newer Clarkdale integrated offerings, but don't natively support dual graphics cards.

For AMD processors, the recently released 890GX is a feature-rich offering, while the outgoing 785GM chipset can be found in some powerful budget motherboards.

How to: Install a new motherboard

1. Back up your data

Motherboard 1

Upgrading your motherboard can cause a few problems for Windows. Not only can it count as a fundamental hardware change, and thus require that you reactivate the operating system, but if the new motherboard is sufficiently different to your existing one, Windows can fail to load at all due to driver conflicts. This is why it's wise to back up your entire system and assume that you'll need to reinstall Windows after the upgrade.

Microsoft's OS has a back-up tool built-in; use this to transfer your files and important settings to an external hard drive.

2. Remove all of the components

Motherboard 2

Turn off your machine, remove the side panel and unplug, unscrew and disconnect everything you see. Everything plugs into the motherboard one way or another, so be prepared to systematically remove it all. Taking a photograph of how everything fits together can help for later.

Take out your graphics cards, memory, processor, cooler, soundcard and any other expansion cards you have. Disconnect the hard drive and optical data cables and unplug the power cables and any chassis cables. Finally, unscrew the old motherboard and put it to one side.

3. Build a base rig

Motherboard 3

The best way of checking that your new motherboard is in full working order is to build a base rig on the box that the motherboard came on.

First, make sure that everything is resting on the antistatic bag that the board came in. Then install the processor, attach the cooler and connect the fan's power cable. Install your memory, making sure you use the right slots (check in the motherboard manual), plug in your graphics card and then attach the power.

Don't worry about your drives at this point. Plug in the keyboard and check that you can access the BIOS.

4. Rebuild the system

Motherboard 4

If the base rig shows a BIOS screen, it's tempting to assume that everything is OK and start screwing your new components into the case.

But before getting your screwdriver out, check through the BIOS and ensure all your components have been identified correctly. If something has the wrong name or isn't showing up, rectifying the problem on the bench is much easier than when everything has been wired into a case.

When you're happy that everything is as it should be, switch the base rig off and begin transferring things carefully into their new home.


First published in PC Plus Issue 296

Liked this? Then check out 9 best PC upgrades for gamers

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