3 - Basic Tests
Basic tests are the ones listed in “Standard Tests” panel of global options of CD-DVD Speed, and are executed in the “Benchmark” tab of the main window.
There are two ways to execute these tests: singularly or all in sequence. Each test can be selected singularly from “Run Test” menu. To execute tests in sequence, the first thing to do is select, in global options, which tests must be ran. Then, it’s sufficient to press the “Start” button.
As seen in introduction, there are five tabs in main window. Here will be given only a list of these parts, but each will be described in detail in its dedicated section.
Benchmark: The section dedicated to all basic tests. This interface is pretty much the same in all versions of CD-DVD Speed.
Create Disc: Starting from version 4.50, was introduced a new section that allows the user to execute a little improved writing disc test. However, the “classic” writing test can be still executed in the “Benchmark” section.
Disc Info: Show some detailed informations about media loaded in the drive.
Disc Quality: The section dedicated to quality test of burned media. Often this test is also called “Scan”.
Scan Disc: The section dedicated to a little different quality test of media.
[BREAK=Basic Tests - Benchmark]
3 - Basic Tests - Benchmark
In this section of CD-DVD Speed it’s possible to execute most of available tests, i.e Basic Tests:
[/li][li]Create data disc (“classic” version; the new one will be described in “Create Disc” section.[/ol]
[BREAK=Basic Tests - Benchmark 1 (TRT]
3 - Basic Tests - Benchmark
Transfer Rate Test
This test measures transfer speed of data and shows results in a graph. In other words, it shows reading speed of data from a disc. This test can be done for two main reasons:
[li]To test a drive (reader or burner)
[/li][li]To test a burned media (CD or DVD)[/ol]If the main purpose is to test a drive, can be used some special discs containing standard defects, like A-BEX discs.
If the main purpose is to test a burned media, the test is aimed at verifying that burning was done correctly and that the media is readable and all data retrievable.
In this test are showed two lines. If colors were not modified by the user, there will be a green line that represents transfer speed, and a yellow line that represents disc rotation speed in revolutions per minute (RPM).
In the bottom scale there is disc capacity, in Megabytes (MB) for CD media and in Gigabyte (GB) for DVD media. In the left scale there is reading speed, and in the right scale there is disc rotation speed (in RPM x 1000).
Under the graph there is a little window containing some extra informations on running tests. For example are reported date and time, test type, reading type, etc.
On the right of graph there is a group of four boxes containing results of Transfer rate Test (TRT):
Current: The current speed during test execution. When test ends, this box changes name and becomes “Average”, i.e. the mean value calculated from maximum and minimum values recorded in the entire test.
Start: The lowest speed detected in the entire TRT. If the reading curve is regular, this value is the same of the starting speed; if the curve is irregular, this is the lowest value recorded in the entire test (see picture).
End: The highest speed detected in the entire TRT. If reading curve is regular, this value is the end speed; if curve is irregular, this is the highest value recorded in the entire test (see picture).
You can see in that picture with an irregular graph, that TRT starts around 7x speed, and ends around 9x speed. In the Start box is shown 1.83x and in the End box it’s reported 13.89 x. These are, respectively, the minimum and the maximum detected speeds in the entire TRT. These values are used to calculate the “Average” speed.
Type: TRT doesn’t measure only reading speed, but also the reading type. There are different modes to read a disc. To understand these modes, it’s important first to describe some basic notions: “Linear Speed” and “Angular Speed”.
In this image the black arrow is the optical pickup route, and the three blue arrows are three different parts of the disc. Each blue arrow represent a segment of a disc track read by optical pickup. All segments run along the same angle, in our example 90Â°, but from the image is clear that segments (tracks) in the more peripheral parts of the disc run along a longer linear distance: 1 cm inner track, 5 cm intermediate track, and 10 cm external track. In the picture all values are given only as an example, and are not absolutely exact.
“Angular speed” is the amount of angle ran along in the time unit when the disc rotates. If a disc rotate at a constant speed, angular speed is constant too, because every part of the disc run along the same amount of angle.
“Linear speed” is the amount of length ran along the time unit when disc rotates. If disc rotates at a constant speed, linear speed vary according the distance from the center of disc. The most inner parts of the disc, near center, run along the shortest distance, and then have the lowest linear speed. The most external parts of the disc, instead, have the highest linear speed because they run along the longest distance.
In optical drives, disc reading starts from the center and goes externally when pickup is moved along a radius of the disc (the black arrow in the picture). If rotation (angular) speed is constant, the most internal tracks run at the lowest linear speed (i.e. are read at the lowest speed), and linear speed increases progressively toward the external parts of the disc (i.e. reading speed increases toward the external).
Optical drives can use four different reading types: CLV, CAV, P-CAV, e Z-CLV.
CLV (Constant Linear Velocity): Reading speed is constant in all disc parts. This means that when a disc rotates tracks run along the same linear distance. Consequently, when optical pickup moves toward external parts of disc, rotational speed is reduced progressively.
CAV (Constant Angular Velocity): Rotation speed is constant and reading speed increases progressively from the center toward external parts of the disc.
P-CAV (Partial-CAV): Rotation speed is constant and reading speed increase progressively up to a certain value. From here, reading speed remains constant, and rotation speed decreases progressively.
Z-CLV (Zoned Constant Linear Velocity): Usually this type is used for writing on a disc more than reading. In this type, writing speed is constant for a given segment of the disc, then increases to write another segment, and so on up to the end of disc.
In each segment, linear (writing) speed is costant, and angular (rotation) speed is progressively reducing; at the end of first zone, rotation speed is increades to allow writing at a higher speed, and so on up to completion of disc writing.
In “Benchmark” window, after inserting a disc in the drive, are showed two other pieces of informations: disc type and its capacity.
For example, inserting an audio disc in these boxes will appear “Audio CD” and disc duration. Inserting a video DVD, will be showed “DVD-Video” and disc capacity in GB. Inserting a burned disc, according to selected settings in global options of CD-DVD Speed, will show the disc type (+R/RW, -R/RW, blank media) or disc booktype (+R/RW, -R/RW, or ROM).
To avoid confusion, remember what settings were selected. If in options is selected to show disc type, a +R disc with changed booktype to ROM will be still showed as +R.
Finally, according to the disc type loaded in the drive, the Transfer Rate Test will show different results.
Data disc (CD or DVD): TRT measure data reading speed.
If the data disc is a dual layer DVD, graph will show two more colored vertical lines. Red line is total disc capacity, and fucsia line is the layer transition. This latter line divides the graph in two parts, and each part is the the reading of a disc layer.
Audio CD: TRT measure Digital Audio Extraction (DAE) Speed.
Blank disc: inserting a blank media it’s measured the writing speed. Writing test will be described in more detail later.
[BREAK=Basic Tests - Benchmark 2]
3 - Basic Tests - Benchmark (continued)
The “DAE Quality test” measures how well the drive can extract audio tracks. This test is done in two parts.
First some audio sectors are extracted to the HD at three different locations on the CD. The same sectors are read again and compared to the sectors written to HD. Depending on the number of differences, the DAE quality will be rated from 0 to 10, where 10 means perfect DAE (no differences).
Next CD-DVD Speed will try to determine whether the drive supports “Accurate Streaming”. When accurate streaming is not supported the drive is unable to locate the requested audio location at any time.
If your drive does not get a perfect score with this test (10/10 and Accurate Stream checked) it is highly recommended to use a CD ripper with a verify function to extract audio tracks.
One of the best CD rippers is Exact Audio Copy.
This test measure access and seek times.
Three measuring are done:
Random: Optical pickup is moved in a random position on the disc.
1/3: Optical pickup is moved from the start of the disc to 1/3rd of the length of the disc.
Full: Optical pickup is moved from the start of the disc to the logical end of the disc, i.e where are located the last data of the disc. The term “logical end” is used because not always the end is in the most external part of a disc. For example, in a disc burned only for half of its capacity, the logical end is where the last data is located, and not in the most external part of the disc, that instead is empty.
Remember: Executed test must be selected in global options of CD-DVD Speed.
What are exactly seek and access times?
In Seek Time test is measured the amount of time necessary to move optical pickup to a specified position on the disc.
In Access Time test is measured the amount of time necessary to move optical pickup to a specific position on the disc plus the time necessary to read a single sector.
Then, access time is always higher than seek time (usually a few milliseconds).
Again, remember: in global options must be selected how many times to execute this test.
This test measure CPU utilization at 1X, 2X, 4X and 8X.
The Burst Rate Test measures the transfer rate from the host adapter to the drive.
Usually an optical drive is connected by the proper cable to the IDE channel of mainboard. In this situation Burst Rate test measure speed transfer of IDE channels.
However, it’s also possible to connect a drive with different interfaces. For example, it’s possible to use an IDE to UDB or IDE to Firewire adapter. in this situation, the Burst Rate test will be useful to determine if the adapter is enough fast to support high speed burnings (this is true mostly for DVD burners).
Important: results are accurate only if the drive caches the data. Since many drives don’t cache audio data it is recommended to run this test using data CDs.
For high speed drives it is necessary to spin down the drive to lengthen the life of the optical parts.
The spin down test measures how long it takes to stop the drive.
The spin up test measures how long it takes before the drive can read data after it has stopped. Shorter times are better.
Faster drives will have higher spin up/down times.
This test will measure the time it takes for a drive to eject, load and recognize a disc.
The time needed to recognize a disc depends on the type of disc. For example a drive needs much more time to recognize a multisession disc than a single session disc.
The eject and load times should always be about the same regardless of which disc is used, because the drive requires the same time to open and close the tray apart from the disc inserted in the drive.
Create data disc
This function will write predefined binary data in a selectable number of files on a blank media. Total file number written on the disc is variable, because data is added until the last sector which makes the disc very suitable to test the read performance, so a DVD will contain much more data than a CD media.
While the disc is created the write performance is shown in the same way as the Transfer Rate Test (TRT). In this case, obviously, the graph is not the reading speed, but the writing speed.
There is also a verify function available which checks the data just written on the test disc. This function must be activated in global settings of CD-DVD Speed.
In versions previous to 4.50, the writing tests were available only in “Benchmark” tab of the main window of CD-DVD Speed. Starting from the version 4.50, it’s available a new dedicated tab (“Create Disc”) to execute a writing test that allows to collect more informations than the “classic” test available in the Benchmark tab. Here will be described the “classic” writing test, and the new one will be described in the dedicated section of this guide.
When executed in the Benchmark tab, the writing test will show in a graph writing speed and disc rotation speed.
Disc rotation speed can be omitted by the graph unchecking the “Show RPM” setting in global options of CD-DVD Speed (See Options --> Transfer Rate).
The “classic” writing test can be executed in two ways, according the selected options (See Options --> Transfer Rate).
Create Data Disc: This function will write predefined binary data filling the disc up to its maximum capacity.
Burn Image File: This function will write the content of an image file (supported types are ISO and NRG) created by user.
To start the test it’s sufficient to select the desired one from the menu “Run Test”
As already said, a verify function is available . If the user wants to use it, it’s necessary to enable it from the global settings. Verification results will be shown in the little window under the graph.
In the “Benchmark” tab, it’s possible to execute all basic tests. These tests can be executed singularly, or in a row.
To execute a single test, it’s sufficient to select that test from “Run Test” menu
To execute more than one test in sequence, the procedure is the following:
1) Select the drive
2) Open CD-DVD Speed global options
3) Select “Standard Test” panel
4) Select what tests must be executed and uncheck all undesired tests
5) Set properly all other relevant settings
6) Insert a disc in the drive. If also a writing test was selected, it’s necessary to insert a blank media or there will be an error
7) Press the button “Start” or alternatively select “Selected” from “Run Test” menu
8) Wait until all tests are completed
9) Save results in HDD from menu “Save” or pressing the little floppy button (number 2 in the pic) to save a screenshot in PNG file
Note: saving only the screenshot will save only the graph, but results of all other tests will be lost. If more than one test is done, I suggest to save from the menu “Save”.
[BREAK=Basic Tests - Create Disc]
3 - Basic Tests - Create Disc
This tab was introduced starting from the version 4.50 of CD-DVD Speed. Basically it’s the same of the “classic” writing disc test of the Benchmark tab, but it allows the user to measure also some more data. In the classic test are showed only writing speed and disc rotation speed, whereas in the new test are showed also drive buffer and CPU utilization, both in the main window and in the plotted graph.
Line colors in the graph can be customized by the user, as already said in the options section of this guide.
Important: All writing settings in global options of CD-DVD Speed are related to the “Classic” test of the “Benchmark” tab. Except for color settings, all options of the new create disc test are located in the “Create Disc” tab (see below for more details).
Important: To start this create disc test must be used the “Start” button. Using commands in the “Run Test” menu will be executed the “Classic” test, i.e. the one executed in “Benchmark” tab and the graph will be not showed if the tab “Create Disc” is selected.
Create Disc main window
This interface is similar to the Benchmark one. In the upper part there is the combo box list to select the optical drive, the little button with gears to open global options, and two buttons, “Start” and “Exit”.
Main part of the window contains the graph.
The scale on the left is writing speed, the scale on the right is disc rotation speed, and the scale in the bottom is disc capacity.
Under the graph there is a progression bar (green bar in the pic), and finally a little window showing some informations on the test.
On the right of the graph there is a panel with various options and informations.
Description of the right panel will be started from the higher part.
Disc info: Show the disc type (+R/RW, -R/RW, RAM), mediacode, and disc capacity.
Settings: This panel contain options that user must set to execute Create Disc Test.
Speed: The writing speed that CD-DVD Speed must use to run test. Available speeds vary according the media used. These speeds are stored in burner firmware.
Burn Image: If this option is unchecked, CD-DVD Speed will write predefined binary data in a selectable number of files on a blank media.
Total file number written on the disc is variable, because data are written until the last sector which makes the disc very suitable to test the read performance, so a DVD will contain much more data than a CD media.
Because data is written until the last sector which makes the disc very suitable to test the read performance, if the user doesn’t have an image file that matches the exact maximum capacity of a media (remember that +R and -R media have a slightly different maximum capacity), unchecking this option is the best way to test a disc at its full capacity.
During disc writing, a graph is drawn showing four curves: writing speed, disc rotation speed, buffer level, and CPU utilization.
If this option is checked, CD-DVD Speed will write the content of an image file created by the user. Supported types are ISO and NRG (the proprietary Nero Burning ROM image file format).
If this option is checked, after pressing the start button CD-DVD Speed will ask to select the image file to burn on the disc.
Writing test will start only after the image file is selected.
Simulate: If this option is checked, CD-DVD Speed will not write any data on the disc, but it will do a simulation. Even if writing it’s not really done, CD-DVD Speed will record all parameters (writing speed, disc rotation speed, CPU utilization, and buffer level) and will create a complete graph.
If this option is unchecked, the disc will be written really.
Simulation can be useful to reveal bottleneck in the data speed transfer through the interface between computer and burner. This can happen, for example, if DMA is not enabled, or if the burner is connected through an IDE to USB (or firewire) adapter.
If data source is an image file, simulation can reveal too frequent buffer emptying due to a heavily fragmented hard disc.
Simulation can also reveal if there is an excessive CPU utilization. This can happen if DMA is not enabled or if there are some processes running in background during the burning (for example an antivirus).
Important: Simulation can be done only with DVD-R and CD-R discs, but not with DVD+R media.
(Thanks to mciahel for providing this info )
Speed: In these boxes are shown the test results.
In the pic are shown there are two series of these boxes: on the left what appears before test start and on the right what appears after test end. Note that the first box initially show is named “Current”, and at the end of the test is named “Average”.
Current/Average: During test execution, this box shows current writing speed. At the end of test it shows average speed, calculated from start and end values (see below).
Type: The type of writing. The various types of writing (CLV, CAV. P-CAV, and Z-CLV) was already described in “Benchmark” section of this guide.
Start: Similarly to what is already described in “Benchmark” tab, start is the lowest speed recorded during test execution. Ideally it’s the speed at which test started.
End: Similarly to what is already described in “Benchmark” tab, end is the highest speed recorded during test execution. Ideally it’s the speed at which test ends.
Buffer: This panel show informations on buffer utilization during the writing test.
A horizontal bar shows graphically buffer status. Next to the bar is shown numerically (as percentage of filling) the buffer status.
Under the bar there are other numbers that refer respectively from left to right the minimum buffer level, the maximum buffer level, and the average buffer level. These values are updated continuously during the test execution.
The little colored square shows the color used to draw the buffer line in the graph. This color can be changed by the user in global options of CD-DVD Speed.
Show graph: By checking this option, the buffer graph will be drawn in the main window. Unchecking this option, buffer graph will be not drawn.
CPU Usage: This panel shows informations on CPU utilization during the writing test.
An horizontal bar shows graphically CPU utilization. Next to the bar is shown numerically the percentage of CPU utilization.
Under the bar there are other numbers that refer respectively from left to right the minimum CPU usage, the maximum CPU usage, and the average CPU usage. These values are updated continuously during the test execution.
The little colored square show the color used to draw the CPU usage line in the graph. This color can be changed by the user in global options of CD-DVD Speed.
Show graph: By checking this option, CPU usage graph will be drawn in the main window. Unchecking this option, CPU usage graph will be not drawn.
Progress: This panel shows in real time the current position of the disc during writing process, and the time past from the start of test.
Sidenote. Regarding times shown in this panel, there is a special consideration. If the user wants to burn an image file, (see later in “Test procedure”), the user must press the “Start” button, and then select the desired image file. Probably some people noted that after pressing the “Start” button, the time counter starts too. Don’t worry: the time of the burning process will be measured only after the image file is selected. In fact, after selecting the image file, the time counter is resetted so the time shown here is the time required to complete the burning.
If the user wants to burn a binary data disc, the time starts after pressing the “Start” button.
To execute the Create Disc test the procedure is as follows.
- Select the drive to use to do the burn.
2) Set correctly all options, both global and specific options
Insert a media in the burner
Check again if local options (mostly if the burn image file option) are correct
Press the “Start” button
Wait until test is completed
Save results in HDD from menu “Save” or pressing the little floppy button (number 2 in the pic) to save a screenshot in PNG file.