Dell Vostro 3400, Service Manual

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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.
Let's take a quick look on the USB evolution referencing to the table below.
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 Super Speed 2010
USB 3.1 Gen 2 10 Gbps Super Speed 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
• 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 3.0/USB 3.1 Gen 1.
8 Technology and components