Dell OptiPlex 3050 All-in-One Owners Manual

All-in-One (AIO) systems supports LCD BIST similar to any other Dell systems that have BIST test implemented. It allows the user to isolate the LCD during troubleshooting to determine which sub-system is at fault. The main difference is the lack of an integrated keyboard scan controller in the AIO. When BIST is initiated, an internal generated pattern from the LCD will be emitted for user's observation. This pattern will go by sequence through this pattern. Black-White-Red-Green-Blue or a White-Black-Red-Green-Blue where each pattern is emitted for 2 to 3 seconds. The following images displays the pattern of the colors on the LCD.

Invoking BIST with user modes

There are two methods to invoke the LCD BIST .

• OSD Toggle
• ePSA

OSD toggle

The first method of user initiation is via OSD toggle button. The user should press the OSD toggle button and hold it in while the power button is applied to turn the AIO on. This is the hardware-initiated method that does not require the CPU and BIOS to be functional. The panel will stay in BIST mode until the BIOS reboots the system. The test duration is approximately 20 seconds which allows 2 cycles of color bar patterns.

To invoke the BIST test via OSD Toggle:

1. Press and hold down the OSD toggle button.
2. Press the power button to turn on the computer while holding down on the OSD toggle button.

ePSA

The second method to troubleshoot is via ePSA entry. The user initiates a Pre-Boot POST via F12 function key and the system enters ePSA. The ePSA menu will have an LCD BIST selection that asserts the proper signals via BIOS commands. The BIST mode will loop for approximately 20 seconds giving 2 cycles of color bar patterns that the user can observe. The time period is controlled by BIOS. After the time period, the BIOS will return the system to the ePSA menu.