Ten ways to speed up a slow PC

2. Reseat the CPU and GPU heatsinks
This is more applicable for the desktop, but the same basic principles apply for a laptop.

There's a small possibility that the thermal conduction between your CPU or GPU and its heatsink isn't optimal, causing things to overheat. If you want to make sure that things are fine, you're going to need some isopropyl alcohol and thermal compound.

Firstly, make sure that the heatsink is attached via mounting holes to the circuit board, rather than directly to the chip. If it appears as if there's no obvious way that the heatsink is held down on the chip, it's using thermal glue or thermal tape to form the bond. If this is the case, ignore and move on, it's unlikely these are causing you issues.

After separating the heatsink from the processor, you'll notice some goop that was last used as a thermal interface. Clean it away by applying a small amount of isopropyl alcohol to a clean cloth and rubbing it until it's gone. Apply a thin but consistent veneer of new thermal paste across the top of the chip (application can be made easier by using a scalpel or old credit card to spread the paste), then reapply the heatsink.

3. Check your RAM and hard drive
There's every chance that your hardware may not be performing to spec, whether through some kind of fault or mere age.

To make sure everything's running as it should, there are quite a few software tools you can use first before you go on an upgrading rampage, or file a warranty claim. Primarily, though, you'll want to check your memory and your hard drive.

MemTest86+ will cover the memory side, ultimately giving you a bootable DVD or USB key to work with to make sure your RAM has no errors.

You might also want to check the SMART (Self-Monitoring, Analysis and Reporting Technology) details of your hard drive. DiskCheckup will do the job for you — head to the SMART Info tab and make sure all the entries in the Status column read OK. You may also want to perform a Disk Self Test. If either of these reveal problems, it's time to back up your hard drive and get a new one.

Solid-state drives
If you have an older SSD (say, from 2009 or older) that doesn't support TRIM (a command that ensures write amplification is minimised), it may very well have degraded in performance due to extended use. The quickest way to return performance is to secure erase it — but, of course, this requires backing things up, and if your SSD is your system drive it's not for the faint of heart. If you're sure that you're not getting the speeds you should out of your SSD, most SSD vendors provide their own refresh tools, or if you want to do it manually there's a guide here to help you on your way.

4. Uninstall everything you don't use
No, really, everything; browser toolbars, programs you forgot about, games you didn't finish. See that system tray in the bottom right stuffed to the gills? Thin it down.

Be sensible — leave things like Windows updates and hardware drivers. If you're not sure what something is, grab a friendly geek or leave it alone.

While you could use Windows's in-built uninstaller, something like IObit Installer will allow you to automate the process somewhat by queuing a whole lot of uninstalls at once.

For most Mac apps (Microsoft Office and Adobe Creative Suite are notable exceptions), you can uninstall apps purely by dragging them from the Applications folder into the trash, and emptying it.

5. Make more space
Hard drives cope better with a bit of free space (as a general rule, 10-percent free should keep things happy). There are two easy ways you can help get rid of things if you've been a bit of a digital hoarder.

CCleaner will help clear away temporary files created by web browsers, install programs and more — and if you haven't done this for a long time (or ever), it can actually make a huge difference. If you're on a Mac, try OnyX.

Space Sniffer, meanwhile, will help you to weed out downloads and files you forgot existed, by showing you a spatial view of what's taking up the most room on your hard drive, allowing you to drill down to the file level, and still access Explorer's right-click menu to delete files. Don't forget you can double click on a folder to zoom in on its contents.

If you're a Mac user, check out Disk Inventory X or GrandPerspective.

6. Defrag
This is mainly a Windows thing. While it won't have that much impact on a modern system, and should absolutely not be performed on an SSD, defragging a hard drive could potentially give you that little extra speed boost you're after.

Under Windows XP you can find the defrag tool by right-clicking on your hard drive in Windows Explorer, selecting Properties and then the Tools tab. Click the Defragment Now button to open the Disk Defragmenter, then click the Defragment button. This can take a long time depending on the size of your storage, so it's best to let it go overnight.

Windows 7 is easier — just click the Windows orb in the bottom left and type defrag, and the Disk Defragmenter application will appear. Click on it, select the hard drive you wish to defrag and then click Defragment Disk.

7. Get a faster antivirus program
Do you run antivirus? Is it old? Some companies of late have really focused on getting system impact as small as it can get, notably Symantec, whose Norton software is now incredibly trim, but is still fighting its old reputation for bloatware.

Performance impact is a tricky metric to cover; however, for best overall performance and speed, we recommend Bitdefender Total Security 2012, followed by Norton Internet Security 2012.

If you're of the free mindset, AVG Anti-Virus Free 2012 provided the lowest average system impact in our tests once scan time was taken into account.

Run a full scan, protect yourself
While we're at it, let's make sure there's no malware on the system that could be slowing your machine down. Run a full scan through your antivirus program, then install Spybot Search and Destroy, update and do a full scan there, too. Run an immunisation when the scan is done, and if you want to be doubly sure, grab SpywareBlaster as well, update and then perform an immunisation there.

8. Update, update, update
Ensure that both Windows and your hardware drivers are up to date — apart from bug fixes, which should make your system work better, you may be getting new features as well. Graphics card drivers in particular should be kept up to date, as performance improvements are introduced frequently.

One tip: don't use the drivers provided by Windows update. These are often cut down, or sometimes don't even work. Go straight to your hardware vendor (be it Nvidia, AMD, Intel, Creative, Realtek, Marvell, Dell, whatever) for the official software.

XP users can run Windows update by visiting update.microsoft.com, Windows 7 and Vista users can use the in-built Windows Update application.

For OS X, just click the Apple icon at the top left and select Software Update.

Don't forget your browsers
While you're at it, update your browsers as well, especially if you're running Internet Explorer 6. Not only will updating your browser get you new features and bring you in line with the latest standards, allowing websites to render properly; optimisations are being made to JavaScript engines all the time, making modern websites faster.

9. Upgrade hardware individually
If you can determine what part is the bottleneck in your system, a simple upgrade will be much cheaper than getting a whole new system. With laptops, your options here are pretty much limited to RAM, hard drive and wireless card, but desktop users will have a little more room to play with.

RAM
If you've got less than 4GB of RAM, investigate adding more — with more moving online, and browsers being particularly memory hungry, having more memory is never a bad thing.

Just be aware that if you have 4GB RAM or more, you'll need a 64-bit operating system in order to recognise and use it all — which for some people still running XP might mean an operating system upgrade as well.

Hard drive
The hard disk is typically the slowest part of the computer. When loading data or if you run out of RAM, your hard drive gets hit — and if it's old and slow, you're going to feel it.

While solid-state drives (SSDs) have definitely addressed the speed issue, they're expensive compared to mechanical hard drives and are much lower in capacity. If you can only afford a mechanical hard drive, make sure to get one that's at least 7200rpm. As a basic rule of thumb, larger capacity drives at the same revolutions per minute are faster than smaller capacity drives.

Graphics
If you're finding games are a bit slow on your desktop, it may be time to update your graphics card. These days, a new graphics card will have significantly more effect on your gaming experience than an updated CPU will.

External, upgradeable graphics on the laptop never really took off — but perhaps we'll see something emerge should Intel's Thunderbolt interface take off.

Wireless
If you're finding the wireless in your laptop slow and unreliable, it's actually quite easy to swap in a new wireless card in your laptop — it uses a standard interface called Mini PCI Express. Just be aware of a gotcha: some vendors like HP will only allow certain wireless cards to be used in their laptops for warranty and support issues. Others, like Dell, will accept pretty much anything. If you've got a laptop that doesn't like alternative wireless cards, you can always get a high-end USB wireless adaptor that should improve performance greatly.

If you've got a friendly laptop, it's a simple case (which, depending on the laptop, may involve removing layers of equipment, admittedly) of disconnecting the antenna wire, removing the old card, putting in the new one, reattaching the wire and then installing appropriate drivers. The hard bit is finding someone that will sell you a decent chip.

Also consider the age of your router — wireless technology is improving all the time, and the more expensive routers generally do provide superior wireless performance. Just remember there's no such thing as a good router brand — stick to models that have had a good response in reviews and online.

10. Last ditch options

Reinstall Windows
Is everything still running slow? It might be time to back up all your files, format your hard drive and then reinstall Windows from scratch. While modern operating systems reduce the frequency with which this is needed, sometimes it's just the only sane way to return things back to how snappy they once were. Plan out at least a day, triple check everything is backed up and that you have some way of getting online in case things go wrong — then dive in.

If you've got a desktop, you'll need your original Windows installation disc. If you've got a laptop, though, you very likely have a recovery partition — somewhere on your hard drive where your manufacturer stores the original state that your laptop arrived in. Usually you can access this by loading Windows's built-in recovery environment, often launched by holding (or in most cases, repeatedly hammering) the proper key from boot. While it can change from laptop to laptop, here's a "rule of thumb" chart for what needs to be done on a brand-by-brand basis to get into the recovery environment.

You should then be walked through the process of recovering Windows. There are usually two options, to keep your files or to wipe everything and start again; despite the time it'll take to set up everything again, you'll most likely get the most speed out of the latter option.

It's still slow!
If all the above didn't work, perhaps it's time to finally admit what you own is old hat, and to get a brand new system with much faster parts and a spanking new Windows 7 64-bit operating system. Or a Mac — whatever floats your boat.

As a positive, if you buy a PC these days, it will last you significantly longer performance-wise than it would even five years ago, and battery life has improved greatly for laptop users. Even price has dropped massively across the board in the last five years.

This story originally appeared as 10 ways to fix a slow PC on ZDNet Australia.

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