Figure 2. Thickness difference
Curved edge
DDR4 modules feature a curved edge to help with insertion and alleviate stress on the PCB during memory installation.
Figure 3. Curved edge
Memory Errors
Memory errors on the system display the new ON-FLASH-FLASH or ON-FLASH-ON failure code. If all memory fails, the LCD
does not turn on. Troubleshoot for possible memory failure by trying known good memory modules in the memory connectors on
the bottom of the system or under the keyboard, as in some portable systems.
NOTE:
The DDR4 memory is imbedded in board and not a replaceable DIMM as shown and referred.
USB features
Universal Serial Bus, or USB, was introduced in 1996. It dramatically simplified the connection between host computers and
peripheral devices like mice, keyboards, external drivers, and printers.
Table 1. USB evolution
Type
Data Transfer Rate
Category
Introduction Year
USB 2.0
480 Mbps
High Speed
2000
USB 3.0/USB 3.1 Gen
1
5 Gbps
SuperSpeed
2010
USB 3.1 Gen 2
10 Gbps
SuperSpeed
2013
USB 3.0/USB 3.1 Gen 1 (SuperSpeed USB)
For years, the USB 2.0 has been firmly entrenched as the de facto interface standard in the PC world with about 6 billion
devices sold, and yet the need for more speed grows by ever faster computing hardware and ever greater bandwidth demands.
The USB 3.0/USB 3.1 Gen 1 finally has the answer to the consumers' demands with a theoretically 10 times faster than its
predecessor. In a nutshell, USB 3.1 Gen 1 features are as follows:
●
Higher transfer rates (up to 5 Gbps)
●
Increased maximum bus power and increased device current draw to better accommodate power-hungry devices
●
New power management features
10
Technology and components
