- Random PC freezes and BSoD errors are the worst nightmares of a Windows user.
- We created this detailed guide to show you exactly what to do during such situations.
- We have covered similar issues in our dedicated hub for troubleshooting System Errors.
- For more great hardware troubleshooting guides, check out our Laptop and PC Fix page.
If you’ve ever assumed there’s nothing worse than BSoD in any Windows platform, we can assure you that there is. Unexpected freezing and rebooting are much worse, especially since they’re, most of the time, the clear sign of hardware malfunctioning.
Is it a RAM, HDD, CPU, or the motherboard? No one but an equipped technician can say with certainty.
Nonetheless, to rush to a repair store is always an option and we advise you to make it the last resort. Before that, take a look at the solutions we provided on this list. Maybe you can fix it on your own, with a little effort.
Even if you don’t, you’ll learn what caused the issue and how to prevent it from happening in the future.
How do I fix a PC that keeps rebooting and freezing
- Inspect RAM
- Check HDD
- Check for overheating
- Double-check drivers
- Update BIOS
- Perform a clean system reinstallation
1. Inspect RAM
- Download MemTest86, here.
- Now, you can burn the MemTest86 to CD/DVD or create a bootable stick drive.
- Plug in the USB or insert the CD/DVD and restart your PC.
- Press F11 (F10 or F12) to open the Boot menu.
- Select the MemTest86 bootable drive or disk and press any key to run it.
- The scanning process will begin on its own.
- After it’s done (and it can take some time), it should give you an insight into the state of your RAM.
Critical system errors are present for ages and the troubleshooting hasn’t changed a lot. If there’s no Blue Screen of Death and your PC is freezing or it’s plagued by constant reboots, hardware inspection is the first thing you should do.
Basically, every single component might affect this, but our main concerns are RAM and HDD.
First, let’s start with the easier one, which in this case is RAM. What you can do is to shut down your PC, unplug the power cable, and open the casing. Once you’re there, remove RAM card from its slot (if you have multiple units, do it for every).
From there, you can switch RAM cards in sequence, or plug them into different unoccupied empty slots.
Moreover, you can unplug one by one RAM card and try running PC that way. Furthermore, you can scan for RAM issues with a third-party tool called MemTest86.
If your RAM is fully functional but the problem persists, move to additional steps.
2. Check HDD
- Download Hiren BootCD, here.
- Burn the Hiren’s BootCD ISO file to DVD or stack it on USB.
- Insert the USB or DVD and reboot your PC.
- Press F12 to open the Boot menu and boot Hiren USB or DVD.
- Now, once the Hiren BootCD loads, choose Dos programs.
- Enter number 6 and press Enter to open Hard Disk Tools.
- To select HDAT2 4.53, choose number 1 and press Enter.
- Highlight your partition on the list and press Enter.
- Select Device Tests Menu.
- Pick Check and Repair bad sectors.
- After the scanning procedure finishes, remove the USB/DVD and restart your PC.
Now, HDD is a serious problem. Even if we neglect the fact that HDD is quite an expensive component, your data is obviously more important. However, too often, the HDD malfunction is the sole reason for freezing and unforeseen reboots.
The same that goes for RAM, is applicable to the hard drive in regards to physical or software troubleshooting.
You can remove it and try it out on another PC or you can use a third-party tool to scan for errors. However, before that, make sure that SATA cable is properly connected.
The physical troubleshooting should be simple: shut down your PC, cut the power, open the casing, unplug the cables, and remove the HDD. Insert it into any other PC and try booting from it. If everything works fine, you can loosen up.
3. Check for overheating
- Clean the PC case. Use something like canned compressed air.
- Don’t use a vacuum cleaner.
- Remove and clean thoroughly the CPU cooling fan.
- Replace a thermal paste.
- Add extra cooling fans.
- In case you have a liquid cooling system, double-check the pump.
- If you’re using a laptop, get a cooling pad or use something to elevate the laptop above the surface.
- That way the air can circulate freely and the overheating should be subdued.
In addition, we can’t overlook the overheating as a possible cause of the issue at hand. Normally, the PC will shut down in order to prevent the damage to CPU after extensive exposure to heat.
However, sometimes overheating can cause PC to slow down, or, as in this case, to fall into a boot loop, freeze, or inflict the unexpected crashes.
Overheating, besides the sudden PSU failure, is the easiest way to completely ruin your PC, so it’s highly advised to track temperature changes closely.
If CPU temperature is above 75-80 degrees Celcius or higher when idle, or above 90 when under stress, you should address it immediately to avoid the fatal damage to your motherboard or CPU.
4. Double-check drivers
- Choose to start the system with the Last Known Good Configuration (advanced).
- In case that falls short, return to Advanced startup options and select Safe Mode with Networking.
- Once the system starts, navigate to Device Manager and update all drivers.
- Don’t let any device or peripheral, no matter how insignificant it looks, to be without a proper driver.
- No exclamation marks allowed.
- You should update and install drivers by navigating to OEM’s website and acquiring them there.
- Once you’re certain that all drivers are properly installed, restart your PC and try booting Windows.
We have accounted most of the physical hardware issues that might’ve been the reason for freezing and crashes. However, if you’ve moved past those, then it’s a valid point that the software is the reason why PC is gradually underperforming.
Or, to make a precise point, some drivers are either not installed or incompatible with the current system version.
The first troubleshooting step, in regards to software, is to access the Advanced startup options and try to start the System with the last known good configuration.
In order to access the Advanced startup options menu, you’ll need to press F8 upon booting. However, sometimes this won’t work due to the fast boot sequence.
In that case, just physically restart your PC multiple times and it should access the aforementioned menu on its own. Nonetheless, if you’re still stuck with the same freezing/boot loop routine, move on to the last two steps.
5. Update BIOS
Besides drivers, there’s also BIOS or rather a motherboard firmware that can cause issues. This is somewhat a cross-road between software and hardware.
If issues emerged after you recently installed a new component supported by your motherboard (make sure to check that indeed it is supported) or after you upgraded OS, there’s a chance that you’ll need to update BIOS to make it compatible for hardware and/or software changes.
Now, flashing BIOS is not a child’s game. But, on the other hand, you don’t have to be an extremely knowledgeable user to perform it. It’s mostly done from the Windows interface but certain novel configurations offer BIOS updates trough BIOS utility.
Either way, make sure to check out this article for a detailed insight. In addition, since the procedure can vary, the best advice is to google your motherboard and look for detailed explanation.
6. Perform a clean system reinstallation
Finally, if you’re 100% positive that hardware is fully-functional and that software is the one that created the problem, reinstallation is an obvious choice. If you’re Windows XP user, that can take some time and effort.
Yet, if Windows 7, 8 or 10 are your cup of tea, the procedure is manageable and not a nerve-wracking experience. The detailed instructions on how to do it in a few easy steps are found in this article so make sure to check it out.
FAQ: Learn more about PC freezes
- What happens when my PC freezes?
During a PC freeze, either the application that you are currently running or the entire system will usually become unresponsive, and even the image displayed on your screen will remain the same.
- How do I fix a PC freeze fast?
The fastest way to un-freeze a PC is to either kill the faulty application through the Task Manager or simply perform a full system reboot.
- Can I lose data because of PC freezes?
It all depends on what you were during when the freeze occurred. Any unsaved progress in apps or unfinished browser downloads will need to be redone later on. Of course, it also helps if you are using a download manager to help you.
With that, we can finally conclude this exhaustive but hopefully helpful article. In case you have something to add to our list of solutions, or an urging question to ask, feel free to tell us in the comments section below.
Editor’s Note: This post was originally published in December 2017 and has been since revamped and updated in April 2020 for freshness, accuracy, and comprehensiveness.