Power-On Self-Test Post, Checkpoint Description

Power-On Self-Test (POST)

Each time you turn on the system, the Power-on Self Test (POST) is initiated. Several items are tested during POST, but is for the most part transparent to the user.

The Power-On Self Test (POST) is a BIOS procedure that boots the system, initializes and diagnoses the system components, and controls the operation of the power-on password option. If POST discovers errors in system operations at power-on, it displays error messages on screen, generates a check point code at port 80h or even halts the system if the error is fatal.

NOTE: When Post executes a task, it uses a series of preset numbers called check points to belatched atport 80h, indicating the stages it is currently running. This latch can be read and shown on a debug board.The following table describes the BIOS common tasks carried out by POST. Each task is denoted by an unique check point number. For other unique check point numbers that are not listed in the table, refer to the corresponding product service guide.

Post Checkpoints List: The list may vary accordingly depending on your BIOS

Bootblock Initialization Code Checkpoints

Checkpoint	Description

Before D1	Early chipset initialization is done. Early super I/O initialization is done including RTC and
	keyboard controller. NMI is disabled.

D1	Perform keyboard controller BAT test. Check if waking up from power management
	suspend state. Save power-on CPUID value in scratch CMOS.

D0	Go to flat mode with 4GB limit and GA20 enabled. Verify the bootblock checksum.

D2	Disable CACHE before memory detection. Execute full memory sizing module. Verify that
	flat mode is enabled.

D3	If memory sizing module not executed, start memory refresh and do memory sizing in
	Bootblock code. Do additional chipset initialization. Re-enable CACHE. Verify that flat
	mode is enabled.

D4	Test base 512KB memory. Adjust policies and cache first 8MB. Set stack.

D5	Bootblock code is copied from ROM to lower system memory and control is given to it.
	BIOS now executes out of RAM.

D6	Both key sequence and OEM specific method is checked to determine if BIOS recovery is
	forced. If BIOS recovery is necessary, control flows to checkpoint E0. See Bootblock
	Recovery Code Checkpoints section of document for more information.

D7	Restore CPUID value back into register. The Bootblock-Runtime interface module is
	moved to system memory and control is given to it. Determine whether to execute serial
	flash.

D8	The Runtime module is uncompressed into memory. CPUID information is stored in
	memory.

D9	Store the Uncompressed pointer for future use in PMM. Copying Main BIOS into memory.
	Leaves all RAM below 1MB Read-Write including E000 and F000 shadow areas but
	closing SMRAM.

DA	Restore CPUID value back into register. Give control to BIOS POST
	(ExecutePOSTKernel). See POST Code Checkpoints section of document for more
	information.

E1-E8 EC-EE	OEM memory detection/configuration error. This range is reserved for chipset vendors &
	system manufacturers. The error associated with this value may be different from one
	platform to the next.

Chapter 4

M5811 specifications

The Acer M5811 is a versatile multimedia desktop PC designed to meet the needs of both home and office users. Known for its solid performance and robust features, the M5811 stands out in Acer's lineup as a reliable option for those looking for a balance between power and efficiency.

One of the key features of the Acer M5811 is its powerful Intel processor. Depending on the configuration, users can choose from various Intel CPUs, including the Core i3, Core i5, or even Core i7 options. This ensures that the system can handle demanding applications, multitask efficiently, and provide a smooth user experience whether for gaming, video editing, or everyday productivity tasks.

In terms of memory, the M5811 supports up to 16GB of DDR3 RAM, which enhances its capability to run multiple applications simultaneously without any lag. This is particularly beneficial for users who engage in resource-intensive tasks like graphic design or programming.

For storage, the Acer M5811 typically includes a large hard drive, often starting at 500GB and going up to 1TB or more. This vast storage space allows users to store a considerable amount of data, from multimedia files to software applications. The system can also come equipped with a speedy SSD, providing faster boot times and improved overall performance.

Graphics are addressed with dedicated NVIDIA or AMD graphics options depending on the model. These graphics cards enhance the visual experience, making the M5811 a solid choice for gamers and those inclined towards multimedia content creation.

Connectivity is another hallmark of the Acer M5811. The desktop is equipped with several USB ports, including USB 3.0 for faster data transfer rates. Networking options typically include Gigabit Ethernet, and many models also feature built-in Wi-Fi capability and Bluetooth support. This extensive connectivity ensures that users can easily connect their devices and peripherals, whether it's external storage, printers, or audio systems.

The design of the Acer M5811 is sleek and modern, fitting well into any environment, whether a home office or a living room. Its compact size allows for easy integration into smaller workspaces, making it an appealing choice for users with limited space.

In summary, the Acer M5811 is a well-rounded desktop PC that offers powerful performance, ample storage, and a variety of connectivity options. Its blend of features makes it suitable for a diverse range of users, from casual web surfing to professional-grade multimedia tasks, making it a valuable addition to any tech setup.