eDay, a national free computer component and phone recycling event, took place across New Zealand on Saturday.
More than 88 tonnes of e-waste was dropped off at seven collection points throughout Otago.
Dunedin City Council waste strategy officer Cath Irvine said in Dunedin there had been a "flurry" of drop-offs early in the day, and it continued steadily.
The waste was mainly personal computers from family homes, but she was expecting schools and other organisations with bigger loads in the afternoon.
By the end of the day, 634 vehicles had dropped off 33 tonnes of e-waste, compared with 621 vehicles last year, and 904 in 2008.
Antique and collectable computers, of which a small pile grew at the Birch St collection point, would be auctioned, with money raised going to help with the costs of the event.
The most unusual item dropped off at Queenstown's Wakatipu Recycling Centre was a virtually prehistoric Sharp computer, complete with two floppy disc drives.
Bought for $7000 in 1981 by a Queenstown man, it would probably be sent to Wellington to also be auctioned by the eDay New Zealand Trust.
It was among the 13 tonnes of waste collected at the centre on the day.
Collections manager Jeremy Bisson said the event was "very successful", with "people very keen to use the service".
During Oamaru's first eDay, 29 tonnes of e-waste was dropped at the Waitaki Resource Recovery Park.
Co-ordinator Trish Hurley said about 75 cars had been expected for the whole day.
However, by 11am there had already been 70 cars, with the queue stretching out into Chelmer St, and by the time it finished 250 cars had dropped off more than 2300 items.
"It was fantastic - a huge success."
In Wanaka, 132 cars dropped off 527 items for recycling, which weighed 5.5 tonnes; in Alexandra, 52 cars dropped off 226 items, weighing 2.6 tonnes; in Cromwell, 71 cars dropped off 170 items, weighing 2 tonnes; and in Balclutha, 46 cars dropped off 268 items, weighing 2.9 tonnes.
The event was established by Computer Access NZ in 2007 in response to growing concern about the volume of e-waste, which contained toxic heavy metals, being dumped at landfills.
Containers of the waste would be sent to Christchurch, where recycling will be managed by the Ministry for the Environment.
