Tested and working. Does not come with operating system or hard drive. Boots to bios with no issues. This HP Pro 3405 desktop tower is a reliable and efficient choice for office and casual computing needs. With a powerful AMD A6-3650 processor and 4 GB of RAM, this unit can handle multiple tasks with ease. The integrated/on-board graphics processing type and optical drive make it convenient for everyday use.The black tower unit has a USB 2.0 connectivity feature and is most suitable for those who need a desktop computer for work or personal use. The HP Pro 3405 does not come with a hard drive or operating system, but it is still a great option for those who want a reliable and affordable desktop.