When it is high, the initial speed of the inner ring of the disc cannot reach the set speed, and a gradual speed-up process is required. Therefore, for a single-sided single-layer DVD with a standard playback time (SP mode) of 60 minutes, the usual full disk recording time is: 4X (constant linear velocity CLV), 15 minutes; 6X (CLV), 10 minutes; 8X (partial Constant angular velocity P-CAV), 8 minutes; 12X (local constant angular velocity P-CAV), 6 minutes; 16X (constant angular velocity CAV), 5 minutes and 20 seconds. In addition, the import and export time of about 30 seconds must be added. It should be noted that the time will be different depending on the burning mode.

Nero burning software can display real-time burning speed (instead of always displaying the selected speed). The method to turn on this function is to open the registry editor after installing the Nero software, and under the HKEY_CURRENT_USER\SOFTWARE\Ahead\Nero - Burning Rom\Recorder item, set the value of ShowSingleRecorderSpeed ??(type is dword, if it does not exist, create a new one). 1. The displayed speed is generally a little lower than the set speed (the difference is less than 0.5 speed).

For the abnormal burning time, we observe the total burning time and Nero’s real-time burning speed, and analyze the reasons as follows.

a) The real-time speed is normal, but the total time is too long

i. Nero data verification is turned on

Features and analysis: the burning process is completed according to time, and then Perform calibration operations. Nero Verification will perform a CRC check on the burned disc at the same speed as the burning speed, which will generally double the total time (unless the maximum reading speed is not as fast as the burning speed - which is possible).

Solution: Nero check often reports that the data is different from the source file, but it is actually used normally. Judging from actual experience, the Nero verification function is not very practical for ordinary users, and this function can be completely turned off (uncheck the "Verify Data" item on the burning speed selection page). If data verification is required, it is recommended to use ScanDisc, PIPO testing, file copyback, etc.

ii. Long import and export times

Features: Import and export actions take a long time (up to several minutes).

Analysis: Some models (such as many models of the LiteOn series and their OEM models) sometimes take a long time to import (more than one minute, less than three minutes) due to writing strategies. This is normal. In addition, some of the reasons for this situation include poor disc quality and difficulty in writing to the inner and outer rings, resulting in slow import and export speeds; some are just accidental problems, such as scratches and contamination of the disc. There are also signs of machine aging.

Solution: First consider whether it is the characteristics of the machine itself. Then try to change the disk to solve the problem. Finally, consider the issue of the recorder itself. Generally speaking, if it was completely normal before, the disc has not been replaced, and the problem persists (rather than never reoccurring) after it occurs, it is more likely to be a recorder problem.

iii. Data that requires encoding and decoding

Features: Non-data disc burning, usually seen in video or audio disc burning.

Analysis: The source file is non-standard data and often needs to be pre-encoded or decoded. For example, video disc source data adopts the formats of RMVB, MOV, and various MPEG4 format files, and audio disc source data adopts the formats of MP3, APE, Flac, and even wav files with non-standard sampling rates and code rates. Generally, video codecs are pre-processed and do not actually affect recording. Some audio encodings are real-time decoding.

Solution: Manually pre-process the source file into a standard format. If the actual recording effect is ideal, you can actually ignore it. At least Nero automatic conversion is very convenient in operation and suitable for novices.

b) Abnormal real-time speed

Characteristics: Nero real-time speed fluctuates seriously, or simply stays at a lower speed.

Analysis: Observe the recorder cache status displayed by Nero to determine whether the writing speed is abnormal due to unstable data flow. Normally, the cache should be no less than 70 for stable burning.

i. The cache fluctuates seriously, and buffer underload occurs from time to time

1. DMA is not turned on

Features: In the device manager, the current transmission of the corresponding channel of the device The mode is PIO Mode4 or Multi Word DMA (an older DMA mode with slow transfer rate).

Analysis: DMA (Direct Memory Access, direct memory access technology) allows the driver to directly access the memory, with fast transfer rate and low CPU usage. How to observe the DMA settings: Open the device manager, and in the IDE ATA/ATAPI controller project, observe the advanced settings page of the master/slave channel respectively. As shown in the figure, the current transmission mode of both channels is Ultra DMA (Mode2 is DMA33, Mode4 is DMA66), indicating that there is a device and DMA is correctly enabled. The current transmission mode is displayed as unavailable, indicating that there is no connecting device at this location. Windows sometimes turns off DMA automatically. It is important to note that the DMA settings of the hard disk and optical drive should be turned on at the same time to ensure smooth data transmission. There is no DMA setting problem with SATA devices. In particular, it is recommended that all machines use 80-pin cables (also known as DMA66/100/133 cables, these terms are exactly the same) to ensure that the ATA66 or above specification transmission mode supported by the recorder can be turned on correctly. Download Solution: Select "DMA (if available)" in the transfer mode drop-down menu, confirm, close, and restart the computer. Sometimes it is necessary to reinstall the motherboard driver. Another solution is to open the PATA controller page, click the uninstall button on the driver page, then automatically search again, and restart the computer after confirmation.

2. The disk is too fragmented or the source file is too fragmented

Characteristics: The burning content is a large number of small files (such as a large number of photos), or the disk has not been defragmented for a long time.

Analysis: Winchester structure hard disk has low random read and write performance. When reading and writing a large number of small files or encountering a large number of disk fragments, there is a huge gap between the read and write performance and the sustained speed.

Solution: Defragment the hard disk partitions with a lot of disk fragments. When burning a large number of small files, it is strongly recommended to make them into a whole image first.

3. Direct copying of discs

Features: Appears in the case of disc copying (on-the-fly burning), and does not use buffering.

Analysis: Once the speed of the disc-reading optical drive is lower than the burning speed due to various reasons (such as poor disc quality), the burning speed will be affected

Solution: Do not use this method method to burn, but first make an image of the original disk. If this method must be used, it is recommended to use full buffering and ensure that the free space of the disk where the cache is located (default is C disk) is larger than the capacity of the source data disk.

4. The system is overloaded and the disk reading and writing tasks are heavy

Features: Burn and run other programs at the same time, especially games, P2P downloads and other software that require frequent disk reading and writing.

Analysis: Even if DMA is turned on, data transfer still requires a certain degree of CPU participation. At the same time, there are too many programs that need to read and write disks, and the disk calls (intuitively expressed as data transmission) that a single program can obtain may be very limited.

Solution: For low-configuration machines, it is recommended to burn without load, that is, without doing any other work during burning. Even if the configuration is better, unless both the disk and the recorder use advanced interfaces such as SCSI, it is still not recommended to run too many tasks while burning. In particular, some programs that frequently read and write disks are taboo.

5. The transmission speed of the external system is insufficient

Features: The recorder uses various forms of external devices and does not use the local PATA port.

Analysis: One more link, one more trouble.

Because external devices need to transmit data through the switching device, the performance of the switching device is also tested. The clear problem is that the 480Mbps (unit byte, equivalent to 60MB/s) advocated by USB2.0 is far from reached, and the CPU usage is relatively high. IEEE1394 (even 1394a at 400Mbps) is better than USB2.0 in terms of speed and CPU usage, but the interface is relatively rare and the transfer equipment is expensive. Poor quality adapters, too long/poor quality cables, and compatibility issues are the most common causes of external drive problems.

Solution: It is recommended to purchase switching equipment with reliable quality; before purchasing, ask netizens if they have used similar configurations and check compatibility issues. If there is a problem with the switching device itself or a compatibility problem, there is basically no real solution. Don’t connect the cable too long, and try to connect the motherboard interface directly with a reliable cable instead of using the front interface of the chassis.

ii. The buffering is stable but the writing speed is abnormal (the cause and solution are relatively clear, so I won’t go into details)

1. The disc quality is poor

2. The recorder is aging

3. Insufficient power supply