SVALT Cooling Dock model DHCR with 2021 14-inch MacBook Pro M1 Max This guide is provided for SVALT reviewers and those interested in learning how to conduct accurate and repeatable supplemental cooling tests. The guide is broken down into the following sections that cover a fundamental aspect of testing:

Introduction to Testing

Conventional benchmark tests typically gauge performance by testing for a few minutes and then comparing test results to a database of previously conducted tests. The process of testing supplemental cooling differs from typical performance benchmark testing in the following ways:

#1 Repeatability
Accurate measurement of supplemental cooling is achieved by conducting two tests with workloads and conditions that are as close to identical as possible. One test is conducted without supplemental cooling as the CONTROL test, which is the test that determines the laptop's built-in cooling system capacity. Another test is conducted with supplemental cooling as the SVALT test, which is the test that determines the impact of supplemental cooling. The VARIABLES, DATA and PROCESS tabs above cover this topic in greater detail.

#2 Throttling
Processor throttling has a dramatic impact on laptop temperatures and performance. If not familiar with throttling, then please read the Throttling page. Tests conducted to measure temperature should avoid processor throttling, while tests conducted to measure performance require throttling to be present in at least the CONTROL test. The TYPES tab above covers this topic in greater detail.

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Testing Types

As described in the Laptop Throttling page, temperature and performance are directly connected and so cannot be easily tested and measured at the same moment in time. Depending on the testing workload and methods used, temperature and performance can either be tested and measured in separate test sessions or within the same test that divides the test results into pre-throttling and post-throttling data sets.

Temperature Testing
Supplemental cooling increases the laptop system's total cooling capacity, which allows the system to run processors at higher power for a longer period of time with little to no throttling. While it may be counterintuitive, the reality is that effective supplemental cooling that reduces throttling can lead to more heat generation and higher processor temperatures because the processors are using more power to run faster and do more work. This means that temperatures in the SVALT test can be as high or higher than the CONTROL test when throttling occurs in the CONTROL test. Without throttling in the CONTROL test, then the SVALT test will have lower temperatures.

If separate tests are used to measure temperatures, then the testing should apply a workload sufficient to generate heat but not so high to induce throttling. Possible tests on Mac laptops with Intel chips might be playing a video downloaded to the local storage drive for one to two hours, while Mac laptops with Apple Silicon M1 or M1 Pro/Max might be run single-core stress tests.

If the same test is used to measure temperature and performance, then the testing data will need to be divided into separate data sets, such as 1) a pre-throttling data set, 2) a post-throttling data set with an increasing rate of throttling, and 3) a post-throttling data set with a steady rate of throttling. Each of the data sets can be tagged with start times in the CONTROL test and then synced up with the SVALT test data to allow for accurate comparisons. At that point each data set can be analyzed for peaks and averages, with the first pre-throttling data set used for temperature comparisons and the third post-throttling-steady-rate data set used for power, speed and performance comparisons. The second post-throttling-rising-rate data set cannot be easily used for comparisons.

Performance Testing
Supplemental cooling helps to reduce heat buildup, however, it can only improve performance when the CONTROL test has enough heat buildup to cause the system to throttle processor power and in turn cause a reduction in temperatures, speed and performance. So to measure performance, throttling must occur in at least the CONTROL test. The time required to trigger throttling can vary from a few minutes to more than an hour, depending on the laptop’s built-in cooling system capacity relative to the laptop’s performance capabilities, the applied workload intensity, and the ambient temperature.

Performance testing can target either the CPU or GPU separately, or can simultaneously target both the CPU and GPU. Some example workload applications and programs are provided below.

Mac Stress Tests
  • CPU for Apple Silicon and Intel: Cinebench Go to menubar File dropdown menu -> select Preferences -> set Custom Minimum Test Duration to the desired test duration, such as 30 or 60-minutes -> click OK -> go to menubar File dropdown menu -> select Advanced benchmark (a checkmark will appear) -> go to the application’s main window panel -> select Custom for the Minimum Test Duration for your previously entered length of time -> click Start on the CPU (Multi Core) for a near maximum system stress test or click Start on the CPU (Single Core) for a less demanding stress test -> click stop after the desired test time duration has completed.
  • GPU for Apple Silicon and Intel: 3DMark Wild Life Extreme Stress Test Go to the application’s main window panel graphics and scroll to the right to find the Stress Test option -> click Start.
  • CPU for Apple Silicon and Intel: Open a Terminal window and run the “Yes” Stress Test command within the following brackets { yes > /dev/null & }. A single instance will run a core at 100%, so can be used to test a single-core or can be repeated to test multiple-cores.
  • CPU for Apple Silicon and Intel: Prime95 Torture Test Go to Options menubar -> select Torture Test -> select Small FFTs.
  • CPU for Intel only: Geekbench 3 Pro Go to Benchmarks menubar -> select Run Stress Tests -> select Limit tests -> set limit to an hour or more.
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Testing Variables and Controls

To achieve useful and accurate results, testing conditions need to be as close to identical between the CONTROL and SVALT tests as possible. This is accomplished by eliminating non-testing variables and setting up tests in a way that can be repeated as easily as possible with identical workloads and conditions. The following are the conditions and variables that SVALT controls for its tests:

Laptop Compatibility
Use a compatible laptop per SVALT’s product page, and to better understand how Apple laptop’s built-in cooling system works, including how it works with SVALT products, see Laptops.

Laptop Setup and SVALT Operation
Setup and operate per SVALT’s Product Setup page. Note that for testing, SVALT metal and heat sink components will absorb heat, so do not setup the laptop with the SVALT product until ready to begin the SVALT test session. Also note that the laptop battery should be fully charged at least an hour before starting tests, as a charging the battery or a recently charged battery can add significant heat to the system.

Laptop Background Activities
There are a number of automated background activities that can consume system resources, generate significant amounts of heat and reduce performance. The following steps can be taken to help ensure that nothing other than the intended test workload is stressing the system, and to help ensure that test workloads are consistent for all tests (note that some of these settings will automatically reset, so check before each test session):
  • Disconnect Ethernet, external hard drives, and any other peripheries not required for testing.
  • Turn off Wi-Fi.
  • Turn off Bluetooth if you are able to use wired keyboard and mouse.
  • Turn off TimeMachine, DropBox and other automated backups.
  • Open OS X System Preferences -> Notifications -> click on Turn on Do Not Disturb in Notification Center -> Open Notification Center from top right of the menu bar -> turn on Do Not Disturb.
  • Open OS X System Preferences -> Displays -> deselect Automatic adjust brightness -> slide to max brightness.
  • Open OS X System Preferences -> Energy Saver -> deselect automatic graphics switch.
  • Open OS X System Preferences -> Energy Saver -> slide the Turn display off after to Never.
  • Open OS X System Preferences -> Desktop & Screen Saver -> Screen Saver -> switch Start after to Never.
  • Open OS X System Preferences -> Security & Privacy -> opt out of automatic reporting.
  • To avoid Spotlight from influencing testing make sure to let the computer run idle for a few minutes after startup or restart. Note that brand new laptops or OS re-installs may requires hours or days to complete the initial Spotlight indexing.

Laptop Fan Control
SVALT supplemental cooling expands the laptop’s cooling capacity to point that the laptop will export cooling from the laptop’s built-in cooling system to SVALT’s supplemental cooling system. That can be beneficial for reducing laptop fan noise and for long term laptop component durability with reduced demands and stresses on the laptop’s built-in cooling system, but it makes isolating and measuring the influence of supplemental cooling more difficult. There are two options, either collect fan speed data and factor that into test results, or eliminate the fan speed variable by matching fan speeds for both the CONTROL and the SVALT test. In the CONTROL tests the laptop fans can run 25-50% faster RPMs compared to SVALT tests that benefit from supplemental cooling. Locking laptop fan RPMs at the CONTROL test’s higher fan speed normalizes this variable. In temperature testing with light workloads, the laptop fans can be left in system default/auto and monitored in case tests need to be repeated. In performance testing with heavy workloads, the laptop fans can be locked at maximum RPM right before the test session begins. Controlling fan speeds is considered an advanced setting and fans should never be allowed to spin at speeds lower than the system default speeds. There are free and paid applications that allow for the fans to be manually controlled.
Laptop Starting Temperatures
Match internal component temperatures prior to starting tests. The easiest way to achieve this is to start the first test at normal working temperatures after conducting some light workloads. This can often be accomplished by setting up the laptop system for testing, opening test apps and arranging windows. Once everything is setup then take a screenshot of internal component temperatures for a reference to use during the next test. After completing the first test, the laptop may need to sit idle or power down for a period of time before matching the first test’s screenshot reference temperatures. This could take minutes to hours. Note that the SVALT product slated to be used for testing should not be used to cool the laptop if it will be used in the second test as aluminum components will absorb heat not associated with the testing workload.

Ambient Temperatures
Match ambient temperatures prior to starting tests and maintain through both the CONTROL and SVALT tests. Since most electrical components generate heat that can be transferred to the environment and laptop (external displays are major emitters of heat), it is critical that external ambient temperature gauges, the laptop and the SVALT supplemental cooling device are all located so that external heating or cooling sources do influence temperatures. To maintain a consistent ambient temperature during testing, an environmental control system zoned for a single room or a manually controlled heating cooling system will likely be required. Note that roughly 75 Fahrenheit temperatures are typically used for SVALT testing. Also note that SVALT review products include an ambient temperature gauge.

Room and Furnishings
Testing on a non-conductive surface is critical to isolating supplemental cooling. Testing on a sheet of rigid insulation is ideal, otherwise testing on empty cardboard boxes can also work. The key is to avoid testing on a surface like a stone, concrete, glass or metal surface. You may also need to move furniture to clear the area around testing.

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Testing Data

Processors change their speed and power at high rates and the changes can be dramatic from moment to moment. These changes have a profound impact on heat generation and temperatures. As a result it is not possible to gather any useful information by watching realtime sensor data or capturing a single moment of testing. The only way to gather meaningful test results is to collect the raw sensor data in log files that can be averaged from milliseconds into larger and more meaningful 1, 5, 10, 15, 30, 60 minute averages.

Laptop Component Monitoring
To test the influence of SVALT supplemental cooling on laptop temperatures and performance, accurate laptop component temperature and power measurements need to be recorded and saved in a format that can be analyzed for comparison.
  • For Apple Silicon and Intel chip Mac laptops, Paddle TG Pro measures and records computer component temperatures in a separate data log file. Go to menubar -> select Show Main Window.
  • For Intel chip Mac laptops, Intel Power Gadget measures and recordes CPU performance, throttling and temperature in a separate data log file. Go to Logging menubar -> select Log to File and confirm there is a check mark.

Testing Reference Data
While the above data sets will be used to calculate test results, it can be helpful to capture additional data for reference. For instance, it will be helpful to capture screen videos, screenshots and environmental photos for time and ambient temperature references. This can help you record testing start and stop times, as well as provide a general test reference for what was tested.
  • Screen capture: Apple’s QuickTime Player records the screen. Go to menubar -> File drop down menu -> select New Screen Recording -> select Record Entire Screen option -> click Record to begin recording. A round circle with square center will appear toward the right side of the top menu bar, which is what you click to stop the recording at which point you can save the video file.
  • Environmental photos: A video, automated photo intervals, or snapshots at the start and other points of the test can be helpful to track testing setups and synchronize test data.
  • Ambient temperature: Multiple thermistors can be used to measure temperatures around the laptop, and remote wired thermistors can be used to measure on surface temperatures.
  • Infrared imaging: There’s a possibility to collect meaningful data if fixed in place with the ability to capture a larger data set, but IR images are more likely to be fun visual representations of general conditions than provide meaningful test data.
  • Apple Activity Monitor provides real-time display and post-test reference through screen videos and shots of system activity (included with macOS) to help you identify non-tested workloads that could result in a test session failure.
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Testing Process

The following provides a sequential step-by-step guide for testing SVALT supplemental cooling. The CONTROL test can occur before or after the SVALT test, but is listed here as occurring after the SVALT test for an easier and much quicker post-test cool down. Either way, a sufficient amount of time is required to allow the laptop to cool down to pre-testing conditions before conducting an additional test session.
  1. Establish a testing ambient temperature that can be maintained throughout both the SVALT and CONTROL tests.
  2. Restrict laptop activities and maintain ambient temperature per the VARIABLES tab.
  3. Open selected testing application and prepare application for test, but do not start test per TYPES tab.
  4. Open laptop monitoring software, arrange sensor windows so that they can be captured in screen videos and screenshots per the VARIABLES and DATA tabs.
  5. Test setup:
    • 1st SVALT test only: Set laptop onto SVALT supplemental cooling device per VARIABLES tab.
    • 2nd CONTROL test only: Match laptop temperatures with the 1st SVALT pre-test temperatures. If temperatures are higher, then wait at idle for temperatures to drop. If temperatures are lower, then apply light workload. See VARIABLES and DATA tabs.
  6. Start all data recording per VARIABLES and DATA tabs.
  7. Adjust laptop internal fan speeds per VARIABLES tab.
  8. Start testing workload per TYPES tab.
  9. After testing workload is complete then end workloads and quit applications per TYPES tab.
  10. Return internal fan speeds and System Preferences to system defaults per VARIABLES tab.
  11. Save data logs per DATA tab.
  12. Test wrap up:
    • 1st SVALT test only: Cool off laptop to return to pre-test temperatures, and then repeat testing for the 2nd CONTROL test with the same ambient temperature and laptop testing conditions per VARIABLES tab.
    • 2nd CONTROL test only: Sort, average, analyze and compare testing data.
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