You might find date of manufacture on the back of the computer.
Computers have many hardware and software components that make up the whole machine, and builders commonly follow a roughly dated sequence when adding various parts. The motherboard or main board is almost always the first component installed when building a PC because it helps other hardware, such as the processor and memory, connect to the operating system. On this motherboard is the basic input/output system chip that performs a precheck of hardware before the OS starts up. If your computer runs Windows, you can use two approaches to access the BIOS information and find the approximate date when your PC was constructed.
Instructions
Command Prompt
1. Click the circular Windows orb logo, also known as the "Start" button, in the bottom-left corner of the desktop. Type "Cmd.exe" in the search box at the bottom of the Start menu. Press "Enter" to open the Command Prompt window.
2. Type the word "debug" where the cursor is blinking in the window. Press "Enter."
3. Press the "Space" bar after the hyphen that automatically appears on the next line. Type the following string of characters, without the quotation marks, after the space: "d FFFF:5 L 8". Press "Enter."
4. Pull the scroll bar to the right, if necessary, to see the date of manufacture stated in the following format: MM/DD/YYYY.
System Information Utility
5. Click the Start button and type "Msinfo32.exe" in the search box at the bottom of the Start menu. Press "Enter" to open the System Information utility.
6. Click "System Summary" in the left pane. Wait for the system details to appear in the center pane.
7. Scroll down to find BIOS Version/Date under the Item column heading. Look across to the Value column to find the manufacture date in the following format: MM/DD/YYYY.
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