Usb Features - Dell Vostro 3681 Service Manual

Table of Contents

Figure 3. Curved edge

Memory Errors

Memory errors on the system display 2,3 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

USB 2.0

480 Mbps

USB 3.2 Gen 1

5 Gbps

USB 3.2 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 3.1 Gen 2 finally has the answer to the consumers' demands with a theoretically 10 times faster than its predecessor. In

a nutshell, USB 3.2 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

● Full-duplex data transfers and support for new transfer types

● Backward USB 2.0 compatibility

● New connectors and cable

The topics below cover some of the most commonly asked questions regarding USB 3.2 Gen 1.

Speed

Currently, there are 3 speed modes defined by the latest USB 3.2 Gen 1/USB 3.2 Gen 1 and USB 3.2 Gen 2x2 specification. They

are Super-Speed, Hi-Speed and Full-Speed. The new SuperSpeed mode has a transfer rate of 4.8 Gbps. While the specification

retains Hi-Speed, and Full-Speed USB mode, commonly known as USB 2.0 and 1.1 respectively, the slower modes still operate at

480 Mbps and 12 Mbps respectively and are kept to maintain backward compatibility.

D15s