"For any site that has that viral growth, it is a challenge to stay ahead of the growth," he said.
Instead of the typical lull in traffic on Friday, Digg.com was getting more visitors and was projected to hit 6 million pageviews, a record for a Friday, Rose said.
But the servers were overwhelmed with the number of users. Digg had planned to add 18 additional servers over the weekend, but decided to push that expansion forward because of the sluggishness of the Web site.
"We made the decision to just take the site down and install the additional boxes right now," Rose said. Digg went offline around noon and was back up close to 4.30 p.m. on Friday.
Digg announced $2.8 million in funding last week from venture capitalists Greylock Partners and Omidyar Network and luminaries including Marc Andreessen. The publicity around the funding has boosted traffic to the site, Rose said.