Consider these pros and cons before unparking your CPU.
Perhaps you’ve heard talk about unparking CPU cores, but you’re unsure of the implications.
Will doing so crater my system?
Will my computer overheat?
What does it even mean to unpark cores, and even if it is safe, is it worth all the trouble?
Is Unparking Cores Safe?
On the surface, yes, unparking CPU cores is safe in the same way that using all eight cylinders of a V8 engine all the time is safe.
Nevertheless, disabling core parking does have some negative ramifications and the potential for problems down the road.
Therefore, it is important to assess the pros and cons before deciding if unparking is something you want to try.
What Is CPU Core Parking?
Central Processing Unit core parking is a pretty basic power-saving concept.
Before diving in too deeply, let’s look at a parallel concept from the automotive industry for a helpful illustration.
Around the turn of the 21st century, automotive manufacturers began getting serious about improving gas mileage due to increased oil prices and tighter regulations from the EPA.
To accomplish their efficiency goals, car companies focused primarily on one technology: variable displacement, which uses a variety of methods to shut off engine cylinders when they are not needed.
Therefore, a muscle car could retain its powerful V8 engine, but it will still achieve some semblance of efficiency.
Conceptually, CPU core parking works the same way.
In 2005, the same year General Motors introduced Active Fuel Management (the company’s iteration of variable displacement), Intel and AMD brought their first multi-core processors to market: the Athlon 64 x2 and the Pentium D, respectively.
Although these were not the first commercially available multi-core processors, they were the first to be widely available and sold at a reasonable price.
(IBM wins the first-place prize with its POWER4 microprocessor released four years earlier.)
The introduction and quick proliferation of multi-core processors gave rise to an opportunity to increase efficiency since not all cores were required at all times.
Just like a V8 Hemi doesn’t need all eight cylinders while the car is idling, a quad-core processor doesn’t need all four cores to complete basic computing tasks.
Therefore, operating systems like Microsoft Windows introduced core parking—a method for shutting down CPU cores when they are not needed.
Doing so became especially important as portable devices like laptops and tablets increased in popularity since more efficient computing equates to longer battery life.
What Does A Parked CPU Mean?
A parked CPU, then, simply means that the operating system has shut down one or more cores of a multi-core processor when max processing power is not needed.
A parked core enters a sleep state known as C6, effectively reducing voltage to zero.
Parking cores reduces energy consumption which, again, increases battery life and has a positive thermal effect on the computer.
When functioning properly, this process of parking and unparking cores should be seamless and not noticeable to the person using the computer.
With parking enabled, the processor cores can switch between parked and unparked states without observable changes.
Cons Of Disabling CPU Core Parking
The most notable side effect of unparking CPU cores is higher energy usage.
Remember, the primary purpose of parking is increased energy efficiency, so it follows that the computer will consume more power with the feature disabled.
As a direct result, your electric bill will be a few pennies higher.
If you’re concerned with increased energy consumption because of environmental concerns, you might want to leave core parking enabled.
The other negatives associated with turning off core parking are all residual issues that arise as a result of higher energy usage.
First is the potential for thermal issues.
With all CPU cores running at all times, the computer will generate more heat than it would otherwise.
If your cooling situation isn’t up to snuff, you might experience overheating which can lead to unexpected shutdowns while you’re in the middle of fragging some noobs or worse: hardware damage from excessive temps.
That said, it is likely the case that CPU unparking will have a small enough thermal footprint to have a negligible effect on internal temperatures, but it is something worth assessing and monitoring.
Do you have enough fans? A big enough heat sink? Enough thermal paste?
If you’re worried, you can monitor CPU temperature with a free utility called HWMonitor from CPUID.
Once you install the software, look under the “Temperatures” item nested beneath the label for your CPU model.
Check the “Values” column for current readings.
What’s a healthy temperature range?
If your computer is idle or under a small load, you want to see temps of around 50 degrees Celsius (122 degrees Fahrenheit).
Regardless of load, you never want the CPU temp to rise above 95 degrees Celsius (203 Fahrenheit), but ideally, temps should stay even lower, around 80 degrees Celsius (176 Fahrenheit) even under a heavy load.
Again, most likely, the computer manufacturer addressed thermal displacement, and regardless of whether parking is disabled or not, all cores will be fully active under a heavy load unless you have a core parking minimum value set (more on this below).
Nevertheless, it is worth monitoring CPU temperature.
Another possible downside to disabling core parking is the potential for a lower overall CPU life as a result of the processor running full bore when the PC is on.
Such a reality, if present, is probably negligible as well.
Modern CPUs are hearty and robust, and even if the overall life of the CPU would be reduced by higher usage, the processor would probably become irrelevant long before the component itself fails.
The last “con” of unparking your CPU concerns portable devices.
By preventing CPU cores from shutting down, the higher energy consumption means shorter battery life and more frequent recharge cycles, leading to a reduced overall life of the battery.
Obviously, this is only a problem when you run your laptop on battery, so the tradeoff may be minimal if you’re never far from an outlet.
Benefits Of Disabling CPU Core Parking
Now that you know the potential risks and downsides, what are the benefits?
Regardless of parking status, your computer will utilize every available core when necessary to complete the tasks required unless you have a minimum core parking value set.
The primary benefit, then, of disabling parking is reducing the amount of latency required to wake up the sleeping cores for utilization.
This process is usually seamless and not noticeable, but when you’re gaming or performing other time-sensitive CPU-sensitive tasks, every millisecond counts.
Another benefit of unparking is peace of mind, knowing that your CPU is running at its full potential all of the time, and is not subject to the whims of a capricious operating system.
Does unparking cores increase FPS?
Opinions are all over the place regarding frames per second (FPS) and unparking.
This is probably because of the variety of processors and software used in testing.
Because of the wide array of possible configurations, it is hard to give a definitive answer, but if some cores are parked all of the time, then you’re definitely losing some CPU power that could give you a boost.
Nevertheless, your GPU (graphics processing unit) is generally more critical than the CPU in determining max FPS, but both variables are important.
Our advice is to benchmark the game you’re wanting to test before disabling core parking, and then measure FPS again after unparking the CPU.
Remember, just because FPS jumped for one game doesn’t mean you’ll see a bump for another game.
Always test and measure.
Does Unparking Really Do Anything At All?
Although the performance bump from disabling core parking might be minimal, Microsoft itself admits that performance can suffer in its write-up on CPU parking in Windows Server 2012 R2.
The article states that re-enabling CPU core parking “can introduce degradation in CPU performance.”
The linked article applies only to that particular version of Windows, but it follows that, in at least some circumstances, it is better to disable core parking.
As the article states, performance is highly dependent on the specific processor installed in your computer, so unparking cores is not a guarantee of a performance boost.
How To Tell If Parking Is Enabled?
There are a variety of ways to tell if core parking is enabled.
The quickest way is by using the Windows Resource Monitor utility.
If you’re running Windows 10 or 11, click on the start button and begin typing “resource monitor” and the application should show up in the search results.
Another way to open the software is via the run dialog box.
Hold down the Windows key on your keyboard and press the “R” key.
Once the box opens, type “resmon” (without the quotation marks) and press the Enter key.
If neither of these works, you can find the executable for the program in %WINDIR%\system32.
Look for resmon.exe and double-click the file to launch the program.
With Resource Monitor running, make sure the “CPU” tab is selected.
On the right side of the window, you should see a graphical visualization of CPU usage for each core.
Examine each CPU graph.
If any of the cores are parked, you’ll see the word “Parked” next to the processor name.
For example, “CPU 3 – Parked” will appear as the heading on the graph.
This method is the quickest for detecting CPU parking, but it only works if you catch Windows in the act of parking.
Resource monitor won’t display parking information if all CPUs are currently active.
For a more definitive answer, let’s turn to the command line.
Open an elevated Command Prompt by clicking the Start button and typing “Command Prompt” in the search bar.
When you see the program listed in your search results, right-click the app and select “Run as administrator.”
At the prompt, type (or copy and paste) the following commands followed by pressing the Enter key after each one:
powercfg -attributes SUB_PROCESSOR CPMAXCORES -ATTRIB_HIDE
powercfg -attributes SUB_PROCESSOR CPMINCORES -ATTRIB_HIDE
What do these commands do?
As you probably guessed, CPMAX and CPMIN stand for core parking maximum and minimum respectively.
These configurations control what percentage of cores are available to be parked.
The problem is that the settings are hidden by default.
These commands make them visible in the Power Options control panel applet which we will look at below.
There are other ways to view the core parking status including third-party utilities and searching long strings in the registry, but this method is the simplest and doesn’t require a reboot or installing any additional software.
To check the core parking status, open up Control Panel from the Start menu and then choose “Power Options” (make sure your view is set to “Small Icons” if you don’t see the power options).
In the right pane, you’ll see your computer’s current power plan.
Certain power plans automatically enable core parking, but regardless of which one you have selected, you can check the parking setting by clicking on “Change plan settings” for your plan and then choosing “Change advanced power settings.”
Scroll until you see “Processor power management” and click the plus sign to expand your options.
Check the “Processor performance core parking max cores” configuration.
If “max cores” is set to 0% then you know CPU parking is already disabled.
You can also check the “Processor performance core parking min cores” setting.
A 100% setting here also means parking is disabled (more on this below).
How To Disable CPU Core Parking
Just as there are several ways to view the parking status of your CPU, there are multiple ways to disable core parking as well, but we’ll list the simplest method first.
Once you’ve followed the steps above to unhide the processor power management setting in Power Options, all you need to do is change the percentage values to unpark your CPU cores.
According to Microsoft, if the CPMinCores value is set to 100%, core parking is disabled regardless of your Max value.
This seems a bit counterintuitive, but the setting is kind of a failsafe because you would never want to park 100% of your cores unless your computer was sleeping.
Nevertheless, to avoid ambiguity, we like to set both the minimum and maximum values to zero.
Doing so ensures that none of your cores will ever be parked.
If your computer is a portable device, you’ll have to change the settings for both “On Battery” and “Plugged In.”
Be sure to click “Apply” after making your changes.
Several developers have created utilities to make the process of monitoring and changing parking states on CPU cores nearly effortless.
If you’d like an even easier way to manage parking, you might try one of these programs.
The Tech Wire does not endorse a specific utility, so as always, do your due diligence before downloading and installing anything.
We think these programs, although nice to have, are not necessary.
One other method worth mentioning involves a preset power plan.
Several Windows power plans automatically disable core parking, but did you know there’s a hidden power configuration called “Ultimate Performance”?
To make the plan visible, we’ll head back to the command line.
Open up an elevated command prompt and enter the following command:
powercfg /DUPLICATESCHEME e9a42b02-d5df-448d-aa00-03f14749eb61
Now head back to the Power Options control panel applet, and you will see the “Ultimate Performance” power plan under “Choose or customize a power plan” in the right pane.
Selecting this power plan (among others) will automatically disable core parking.
We still like to unhide the core parking max and min settings to be sure that the CPU is unparked.
Should You Unpark Your CPU Cores?
Now that you know how to disable parking, does that mean you should do so?
Weigh the pros and cons above, but if your primary concern is maximum processing power at all times at the expense of excess power consumption, then you should ensure core parking is disabled on your computer right now.
However, if you have concerns about excess power consumption or thermal issues, then it may be better to leave core parking enabled.
If battery drain is your worry, don’t forget that you can configure different parking settings while unplugged vs. plugged into AC power.
Edit your power plan using the Power Options applet as described above and set the desired min and max values for “On Battery.”
Conclusion: Is Unparking Safe?
As you can see, in general, unparking CPU cores is totally safe.
While there are some side effects that you should be aware of and monitor, disabling core parking is not going to crash your computer or damage your CPU unless your system has some serious cooling issues.
If you want to unpark your CPU, keep an eye on processor temperatures, battery drain, and energy consumption, and your PC will be just fine.