The two rivals, which provide engineers with equipment like batteries, cables and computer consumables, said interest in the Raspberry Pi -- a single board computer as powerful as a smart phone that can be plugged into a TV, keyboard and USB devices -- had reached hundreds of thousands since its February 29 release.
Electrocomponents and Premier Farnell were chosen as sole distributors of the new product because of their access to customers in the engineering sector.
The tiny gadget was developed by the UK's Raspberry Pi Foundation, created by a group of Cambridge University teachers in 2006. It costs between $25 and $35, can run games and spreadsheets, and aims to revive flagging next-generation interest in programming and help raise the profile of computer science studies in schools.
Budding programmers will be able to write programs for the computer board, or learn how to do so with tutorials, as well as run high-definition video content, digital images and connect to the internet.
An initial batch of 10,000 were snapped up well inside the first day, with Premier Farnell's website counting around 500,000 hits every 15 minutes. Both firms said interest, now in the hundreds of thousands, had remained strong and that while it was unlikely to be a profit driver for either, it was attracting new customers.
"It's been phenomenal. It really opens up the world of programming to a mass market," Premier Farnell's Chief Financial Officer Nicholas Cadbury told Reuters.
Glenn Jarrett, head of electronics marketing at Electrocomponents', said it had never previously experienced such levels of interest in a product with more than 200,000 registrations across its websites already.
The firm said strong interest in the UK and Europe had now spread to the United States and Asia where the group will soon take a Raspberry Pi to a prominent electronics trade fare in China.
"It has certainly captured some hearts and minds," Jarrett told Reuters. "It globally engages with the people who are most interested in technology, and that is absolutely at the heart of our customer base and the type of customer we want to chase."
Currently sold without casing, its no-frills basic design won't be worrying fancy tablet producers any time soon, but that was never the intention behind it, one of its developers told Reuters.
"It is replacing the Spectrum, the Commodore 64, this class of machine that used to exist and really doesn't anymore," said Eben Upton, who was part of the group of Cambridge University teachers that began developing the idea via the Raspberry Pi Foundation.
"It comes with the tools you need to start programming, from very introductory levels up to professional ones," he said.
Upton said the foundation was talking to government about a mandate to have computer science taught in schools with text books and tutorials used alongside the Raspberry Pi.
The foundation said it had also received interest from developing countries looking for cheaper alternatives to traditional PCs in hospitals, museums and schools.
The first batch of Raspberry Pis, currently being manufactured in China, are expected to reach customers in two to three weeks with subsequent orders due to be met in around six to eight weeks.
Having originally planned to make just 100 computers and hand them out to prospective Cambridge students, Upton said the six-strong foundation were "punch-drunk" at the reaction and would use it to help fund an educational software release later this year, and promotions at grassroots and government levels.
"Building this computer isn't the end, it was the enabler that we needed. The real goal is to educate a new generation of computer programmers," Upton said.
(Reporting by Neil Maidment. Editing by Jane Merriman)