(CNN) -- Raspberry Pi, the tiny, ultra-cheap, Linux-based PC, went on sale Monday in the U.S. through retailer Allied Electronics, but it's already out of stock.
The A version of the computer, which only costs $25, has 256MB of RAM, a single USB 2.0 socket, an HDMI, SD card, and 3.5 audio sockets, but no Ethernet port. Available only through Allied, the A is now completely out of stock for U.S. customers.
The $35 Raspberry Pi B is also out of stock at Allied, but it can be bought through Newark, another retailer, which only carries that particular model.
The Raspberry Pi's more powerful version has 512MB of RAM, two USB 2.0 sockets and an Ethernet port.
Both the A and B are equipped with an ARM processor and are amazingly small — approximately the size of a credit card — making them suitable for a variety of applications in education and DIY systems.
Raspberry Pi A launched in Europe in February of last year to heavy demand, followed by a launch in Asia last week.
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