Home-baked computing just got a little cheaper: The next-generation Raspberry Pi A+ data processor is available now for $20.

A step up from the original Model A, this low-cost variant comes after the summer release of the $35 Raspberry Pi B+.

Like its predecessor, the Model A+ users the BCM2835 application process, and comes with 256MB of RAM, but is significantly smaller, consumes less power, and boasts a number of improvements.

Weighing in at 65mm in length (versus 86mm for the Model A), the A+ comes with a 40-pin GPIO header, and is compatible with the HAT standard for add-on boards. It has also replaced the old friction-fit SD card socket with a more modern push-pin micro SD version. And, like its B+ cousin, has a new audio circuit with a dedicated low-noise power supply.

"When we announced Raspberry Pi back in 2011, the idea of producing an 'ARM GNU/Linux box for $25' seemed ambitious," Raspberry Pi founder Eben Upton wrote in a blog post.

"So it's pretty mind-bending to be able to knock another $5 off the cost while continuing to build it here in the U.K., at the same Sony factory in South Wales we use to manufacture the Model B+," Upton said.

Computer hobbyists in the U.K. can pick up the $20 Model A+ from Farnell; U.S. consumers can look for it online via MCM.

Check out the new mainframe in action in the video below.

In July, the Raspberry Pi Foundation introduced its Model B+ computer, with four USB 2.0 ports and a Micro SD socket, as well as a tidier layout and other improvements over its two-year-old predecessor.

Some things, however, remained the same, including the BCM2835 application processor and 512MB RAMand its $35 price tag. The Model B+ is still available from various Raspberry Pi dealers, including Farnell and RS/Allied Components.

For more, see PCMag's review of the original Raspberry Pi and the slideshow above.

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