The raiders escaped with Sun Microsystems chips worth a total of £40,000 from the offices of Express Newspapers in central London. The processors were stored in the company's systems room, which was previously thought to be secure.
Police are investigating possible links with other similar chip thefts.
IT departments have already been warned to improve security following concerns that they are increasingly being targeted by criminals.
Detective constable Spencer Barnett of Walworth CID said, "We are asking IT departments to make sure that they have adequate security, that doors that should be closed are closed and that there is film in the security cameras.
"We are aware of a number of similar thefts of what is quite an unusual component. This is an ongoing investigation."
A gang of between seven and 10 youths aged in their late teens, all wearing dark clothing and baseball caps, overwhelmed security guards at the Express building in Southwark on 19 August.
The entire raid took just two and a half minutes.
The removal of the memory chips is believed to have crashed the building's IT systems and affected production changes on late editions of the following day's Daily Express. The offices are also home to the Daily Star, celebrity magazine OK and a number of adult publications.
A Scotland Yard spokesman confirmed that detectives are investigating possible links with a number of similar thefts. Officers are studying footage from security cameras at the Express offices and have gathered forensic evidence.
The gang's methods are similar to those used by "steaming" gangs, whereby large groups of youths target off-licences, jewellers and banks and overwhelm staff by sheer force of numbers.
A spate of IT robberies have been reported along the M4 corridor this year. On at least one occasion the robbers were armed with a gun.
In January, a police spokesman reported that computer chips worth a total of £18m had been stolen over the previous 18 months in the south of England alone.
Earlier this year members of a gang branded the "Men in Black" were convicted of burglaries in offices across London. The smartly-dressed men mingled with genuine staff to reach the systems rooms, where they removed Sun chips.